Wouldn't you also need a PSX emulator that can hook into the PocketStation emulator? I know that some games like FF8 won't just write to any card assuming it's a PocketStation and actually need the PocketStation to boot up before they will transfer any data to/from it, meaning the PSX emulator will either need to have a built-in PocketStation emulator or support linking with one... in which case said PocketStation emulator would also need to support linking to a PSX emulator.
I tried doing that a few years ago with PK201, the only PocketStation emulator I could find for Windows that was supposedly halfway decent. Problem is it hasn't been updated in forever (Not even clear when it was, filename suggests 2020 but all the files inside have a filedate of 1999), is closed source, Japanese, and only links up with a PSX emulator I had never heard of called Xebra which is also closed source and made by the same creator, last updated in 2022, and the creator has since dropped it and is no longer working on it.
I tried to use it and it was just an exercise in frustration.
I know that NO$GBA and MAME support it, but IIRC they have no PSX emulator link compatibility with their own PSX emulators. At this rate we would need either a PSX emulator dev to make one (good luck with the Duckstation guy) or have them add a hook/link option so someone else can make a separate PocketStation emulator that links to their emulator.
This is unfortunately a situation where you would have to emulate what are basically two entirely different systems, even with entirely different CPU architectures, yet link them together.