Your fightstick should work on the PS5 if it is licensed by Sony, has a PS5 compatible PCB, can accept a PS5 compatible PCB, or can accept a PS5 adapter. The best PCB for PS5 compatibility is the Brook UFB Fusion. Simpler PCB solutions would be the Brook P5 Plus or Brook P5 Mini.
If you are looking for an adapter for your fightstick’s EXT port, check out the Brook Wingman FGC. If you have an older fightstick that comes with the Brook Universal Fighting Board (UFB), you can attach the Brook UFB-UP5 to it for PS5 compatibility. You can also check out our lists of the top PS5 fightsticks and top PS5 hitboxes.