As indicated by label. What would the results of Willem II, prince of Orange, surviving be. He doesn't have to survive all that long - simply until his son has reached his majority (thus butterflying the factionalism that split the Orangist party when his mother and his wife started arguing).
Thoughts?
First, that's a knock-on, not a butterfly effect. Utterly predictable.
Second, William's longer life has drastic effects on Dutch internal politics. 1650 was the height of William's quarrel with the States, which was approaching civil war. With his death, the States became supreme and the Netherlands a
de facto republic.
If he live, that eliminates the First Stadtholderless Period. Either he makes the stadtholdership hereditary with quasi-royal powers, or the States cut him down. There could be fighting - William tried to seize Amsterdam by force.
Suppose he succeeds. That in turn changes Dutch foreign policy in those decades. The Dutch may still fight England in the 1650s; William is strongly sympathetic to the Royalist cause, being married to Charles I's daughter.
But it is unlikely that the Dutch will fight England after the Restoration.