This idea has really captivated me, and as such I refuse to let this thread die.
With a POD of Prince Philippe having a change of heart in let's say, mid 1889, the engagement announcement by that Christmas, with the couple married in late 1890, there's going to be some immediate reactions across Europe.
In
Germany, Bismarck is already out of power by this time, ousted by both newly-raised Emperor Wilhelm and by the Catholic Center Party which has taken control following the 1890 elections. The German Chancellor is now Leo von Caprivi, and between him and Wilhelm the course of Germany's
Neuer Kurs are soon clear with the 1890 Anglo-German agreement. I think the real change would be that, with a royal wedding tying the British royals and the Orléanists in mid-1890, it's clear much earlier than IOTL that France's diplomatic isolation is either at the end or near-to it, so the German-Russian Reinsurance Treaty is renewed in late 1890. von Caprivi is very likely still going to lose power when he tries to reintegrate the Catholic church into the German education system and is blocked by the other major parties. Here, Wilhelm appoints the young and very conservative Botho zu Eulenburg, the Prussian Prime Minister, as Chancellor, as opposed to IOTL where he passed over him and appointed the aged and fairly moderate Chlodwig, Prince of Hohenlohe to succeed as Chancellor. Eulenburg had a very Bismarckian outlook, but IMO wise enough to defer to the Emperor on most matters of importance. As such we're looking going to see the Anti-Socialist Laws renewed in 1891 (IOTL they were allowed to expire).
Now, come the 1893 elections I think the Social Democrats would do even better than they did IOTL, due to the perceived failings of
all the other major parties - The Center for the education fiasco, the National Liberals and Conservatives for the issue of France, and for maintaining an alliance with Russia while trying to integrate themselves with the British while those two nations have a growing rivalry, and all the parties for continuing the highly unpopular Anti-Socialist Laws - and might even be able to translate that into real gains ITTL. IOTL while the Social Democrats won the plurality of the vote, due to the German electoral system which unequally favored rural constituencies they only gained a fraction of seats in the Reichstag, an issue that plagued the party in every election from 1890 until 1912. ITTL however in general I see the left doing better overall, with the Social Democrats, Free-Minded People's, and People's parties making solid gains in 1893, while right-wing parties like the Conservatives, National Liberals, Free Conservative/Imperial, German-Hanoverian, and Bavarian Peasants parties doing much worse ITTL. This means Eulenburg either is forced to bring the Social Democrats into the government coalition, or has to make a very broad alliance of of very different groups in order to avoid the first option. Either way I don't think he would be up to the task of keeping the parliament on track 100% of the time, and so I see the Reichstag spending more time working on 'socialist' measures like finally defeating the Anti-Socialist Laws and likely extending some of Bismarck's state socialist measures, which isn't gong to please Wilhelm at all as he wants to focus on colonial adventures and building up his pet navy.
As such sometime around early '97 he'd likely remove Eulenburg and appoint someone else as Chancellor who'd be more 'iron fisted' in enforcing the Emperor's will on the fractious parliament. IMHO he'd likely go for someone like Alfred von Waldersee, who had been calling for even harsher measures against the Social Democrats for sometime, and who had already been burnt by Wilhelm once and thus knew what it would take to work with the young hot-headed Emperor. However when von Waldersee and his few conservative allies tries to force through an extension of the Anti-Socialist Laws, he's decisively defeated by not only the Social Democrats, but also members from the Center party which break ranks over the issue. The whole thing turns into a major crisis which completely changes the German political map and brings the German government to a standstill until the 1898 elections, in which the right-wing parties are decisively defeated and it becomes obvious that it would be impossible to form a government without a coalition of both the Social Democrats and the newly constituted Independent Center. Wilhelm tries to rule by decree without either a Chancellor or the approval of the Reichstag for a time, as he's already turned much of the Bismarckian machinery to his disposal earlier in his reign, such as making the various cabinet ministers answerable directly to the Emperor, not the Chancellor (or the parliament), but this ultimately fails as the parliament continues to shot down any legislation he proposes, and those who would side with him are too small of a minority. Finally, Wilhelm is forced to back down in face of mounting public pressure as well as on the advice of his British family members, and appoints a new Chancellor - the relatively unknown Friedrich Krafft von Crailsheim, Minister-President of Bavaria - who is acceptable to all sides involved.
This means that Germany is asleep at the wheel when the Orléanist Restoration takes place in Paris in 1899, and by the time the Germans have their feet underneath them again, the French are just as stable and organized as well.
As an aside, this also means that the German colonial empire is much smaller; Germany would likely be less involved in putting down the Boxer Rebellion, and so the German concessions would be smaller, if they existed at all ITTL. As well following the Spanish-American War the Caroline & Northern Mariana Islands and Palau likely go to, either in total or divided between, Britain, Japan, or the US, while the US definitely picks up all of the Samoas, instead of those islands being sold to Germany. On the other hand German Togoland would retain the Yendi and the Volta Triangle since they would never be traded away to Britain in return for the pacific colonies. So a smaller, but more compact, more concentrated colonial empire.
EDIT: Oh, and no German Naval Laws.