After making $500M, moving devs will be trivial. Like the potential employee compensation alone will have people all over wanting to work at Pocketpair, let alone the idea of a buyout.
Also, there is no injunction in place so Pocketpair atm is free to do whatever a company can. The court case itself will take many years.
No, patents are only valid in their own jurisdication and each sovereign has its own court system to determine the validitiy of the patent. Treaties can help international enforcement though the only two countries with enough economic power to effectively do that is US/China.
There is the EU wide patent system, afaic, Nintendo have not filed a lawsuit there.
The two biggest Palworld markets are China and US.