Re: Buy once for different platforms PC/Playstation

No. You'll have to purchase the game on both PS4 and PC to play on both.

That said, once Squadrons becomes available in the EA Play (non-Pro) Vault, you'll be able to play on the PC and Xbox if you have Game Pass Ultimate (which includes the regular EA Play) and you won't even have to buy the game, but I guess that won't cover your Playstation.