Staying in the Netherlands is probably the safest, as he could marry one of the younger daughters of Frederick Henry, but seeing him go on to Denmark or even Sweden is also pretty interesting. Maybe even in Courland? Jacob Ketteler had a few daughters, and they married quite well (a Landgravine of Hesse-Homburg, another of Hesse-Kassel) despite Courland's far afield position. As long as he remains in a Protestant state, I don't think finding him a wife would be too hard, as there would plenty of suitable German Princesses I think, even if of minor houses.
So then we assume Edward has a son, I'll go with Edward as well, with whoever he marries. Young Edward grows up wherever his father is, the Netherlands, Denmark, Hesse, Brandenburg, wherever. In 1685 he inherits from his cousin Charles II and becomes Elector Palatine as Edward I. The French invade in 1688 and he's in exile again, presumably going back to the Netherlands or wherever. Seems like the Nine Years' War would follow similar to OTL, unless this Edward is some kind of military genius and leads an army of protestant northern Germany against the French. Assuming he isn't the French pursue their scorched Earth policy in the Rhineland and when Edward finally gets it back after Ryswick in 1697 its completely devastated.
So Edward I begins the long process of rebuilding, ruling in a state that's seen almost all its cities destroyed and most of its population killed or forced to flee. Seems like the Act of Succession or something similar to it would probably follow shortly making him heir presumptive after Princess Anne, to King William III. So at this point Edward I is in his fifties (assuming he's born around the same time as Edward's children with Anna Gonzaga), so he's married by now and his kids have to be adults approaching marriage. Let's say he has at least one son, I'm going to call him Frederick to avoid confusion.
So I wonder if Edward I doesn't just go to England. What's to keep him in the Palatinate? After his experience with the Palatine Succession he may want to take extra steps to secure his position. This way Frederick can also be groomed as a future heir to the throne. Frederick's marriage will probably also be contracted with this in mind. On the other hand will the British really like the idea of an heir
presumptive moving in like that. It is a bit... well presumptive, frankly. I suppose a lot depends on his relationship with William and Anne. This may come to a head in short order when the Palatinate is once again invaded by the French during the War of Spanish Succession. Should Edward or Frederick attempt to pressure the British into defending/recovering the Palatinate it may exacerbate those tensions. Then again given the threat of the Jacobites and in order to secure a protestant succession the British may welcome Edward and Frederick in order that their succession is handled smoothly. Certainly good behavior and a certain degree of respect and deference to British traditions would be necessary to sustain a favorable reputation for the Palatines through the reign of Queen Anne.
Either way it seems possible that Edward may not live to see the end of the War given his age at the time (mid-late 60s). So he may end up like OTL Sophia, dying just before Anne and never succeeding her. The difference is that his son, for better or worse, may have already spent several years in England before becoming King. As for the Palatinate Edward would have only ruled there since 1697 (Ryswick) and of that he only resided there for the first four. So would either Edward or Frederick really be that attached to it?, at least as compared to George and Hanover. Out of necessity and for lack of interest it seems like it will go to a second son as soon as one is available. Indeed that may be incorporated into the Treaty of Utrecht or its equivalent it Frederick has a younger brother or a second son by that time.