It's a borderline case. However, for anything such as this to occur, the POD would have to be far beyond the Spanish-American War to create that change.
I think this is an interesting question because it had proponents both in the US and the Philippines. One can safely assume I think that if the Philippines had gotten statehood it would have been divided into 4 or 5 states. I think this would also lead to some interesting migration patterns, the Philippines would probably be much more diverse than it is now. What do you all think? Is such an idea feasible? How would WW2, the Cold War, and modern day America be different? Not only that, but would this mean that perhaps Lucas Miller's idea to rename the USA to the United States of Earth would be taken more seriously?
Now, my determination for what would be necessary for any American foreign adventures is a healthier result in the Civil War. The US cannot take the human costs and collateral damage and still be willing to act overseas. Furthermore, there is the issue that the Philippines are not primary to defense of the metropole, of which Hawai'i could easily be shown to be (the Hawai'ian islands are the closest islands to the west coast of any large size, and have a low population). In comparison, the Philippines have a large native population that are on the periphery of American interests.
Frankly, the US must be more invested in the Pacific to even consider annexing the Philippines; there's no reason for the US to go out of their way to integrate such a large and foreign population. Remember, the point of interest the Philippines have is Subic Bay and the harbor there.
There was some interest of acutually integrating with the American metropole, but at the same time, the Philippines just wanted the same thing as they wanted with Spain. They wanted to be considered of the same class of citizens as the homeland. It was either that, or they wanted independence, and the decision will have to be made soon after the annexation of the Philippines.
Something that might help is that the US did not originally plan to take all of the Philippines. Only Subic Bay was desired, so only Luzon was initially sought. So, if the US takes only Luzon, then they might have a chance to retain it. (OTL, Luzon had a population of 2.580 million in 1887, and 6.686 in 1932. That is 51% and 49% of the total population of the time. Take the average of the percentage, and it is safe to assume that roughly half of the population is located on Luzon in the time frame listed. So, in 1900, the estimated population of Luzon is 3.708 million out of a total of 7.409 million.) This population is quite a lot higher than Puerto Rico, but it is much more manageable and concentrated in Manila and nearby areas.
So, here is my advice if you want to have the US actually make the Philippines part of a state is as thus: Have the US far more invested of the Pacific, with them desiring a second Hawai'i of sorts in the west to guard an American Lake in the Pacific. This requires that they view Oceania in general as part of the Western hemisphere, and a more adversarial look at Great Britain helps. The Civil war ends earlier, the Alabama claims aren't resolved as well in the US's views and the reconciliation takes longer to start. The US begins looking overseas much earlier after the war, and starts furthering its claims in the Pacific (Guano Island claims et al). Perhaps the Colony of Ellena/Kingdom of Ambong and Maroodoo succeeds and acts as a coaling station for the US, resulting in US desires for a port that is US territory instead of belonging to an American Rajah. Regardless, the US must be more aggressive and assertive in the Pacific. The Line Islands would have to be successfully claimed in total; the US might move into the Marshall Islands unofficially. Perhaps a bit of a kerfuffle over the Washington/Marquisas islands as well. US goes all in on Samoa earlier. Then, once the Spanish-American war occurs (not the same one, but one is likely inevitable), the US eventually goes in and, instead of Guam and the Philippines, they take the rest of the Carolina and the Mariana islands plus Luzon. That way, you have Luzon be the western citadel opposite Hawai'i and central to US Pacific ambitions. This gives the US a
reason to go out of their way to keep Luzon, even if it involves giving up concessions to the region and put them on the path to independence.
It also helps for the US to move in before the First Philippine Republic is proclaimed. The remainder of the Philippines would likely be sold to Germany by Spain after said war (I think Germany will form, even with this PoD).
Also, a more adventurous US would be somewhat more agreeable to the annexation of foreign subjects, especially if the idea is to actively deny another power control of a region deemed vital to the US. So, in this case, you have a US agreement to integrate Luzon, at the least, as opposed to the OTL deal to establish a Philippine republic after a certain amount of time.
At the same time, there would be an incredible amount of pushback, both because it is rather blatantly imperialistic, of which the US was opposed to overseas, historically, and due to the racial and religious makeup of the islands. It's one thing to support a rebellious population of Anglo settlers against a Spanish-speaking Catholic government, but to do the same to liberate such distant, populous, foreign region would be difficult for the US to swallow. That's part of why having this occur before the First Republic is important (it reduces the image of oppression), while having a successful Ambong in addition to Sarawak would help as well: if the two adventurer states carved out of the Bornean jungle can successfully introduce civilized behavior and the English tongue to those remote islands, then assuredly the US would be just as capable of doing so. (Yellow journalism comes into play here, as the successes would be hyped beyond what actually occurred).
That gives a rough outline for what I believe would be necessary just for the US to have a shot of integrating
part of the Philippines. At best, the remainder of the islands might come if a Great War variant ever happens and the US moves in, although the Sultan of Sulu might be restored in the South (the US did have relatively good relations prior to the annexation, and they may not want the headache involved with ruling those areas). As for what it would involve, relative to foreign policy? It would make the US a lot more sensitive to Asian concerns. A Great War probably would occur in some point (even if it is just a general European war that spills over worldwide), but it is quite a major question as to whose side the US would take. The US moving so deeply into Asia and taking such a large chunk of Oceania would both bottle up the Japanese and agitate US/UK relations, so the US might find itself more at odds with the UK in this timeline. The reconciliation isn't impossible to halt at this point, although it is still difficult due to the integrated economies of the US and the UK and the shared language and culture, combined with a determination to demilitarize the large borders involved. So, by that point, it is anyone's game.
The Philippines, though, would likely end up far more developed than OTL, being the location of major naval bases. The population would likely be quite a bit lower, though, as the islands develop, though they'd still become quite populous and one of the largest states in the country. It's doubtful that the US would change its name, though; the concept of Oceania as a continent may not develop, or the continental line might be drawn to only include the large islands from Australia, New Zealand, Fiji, Vanuatu, the Solomons, and east. And, as there is no other country that contains the word America in their official name, then America would likely remain the demonym. This may last longer in the case of a divided Philippines, with Asian Filipino and American Filipino being the obvious difference.
tl;dr, the US in OTL would not have ever let the Philippines join as states OTL without changes far back in history that would make the US more amenable to Catholic, Spanish-speaking Asians join the country as a sovereign state. The changes required would likely result in a 20th century that looks far different, and it would not be one you'd recognize.