It’s not an emulation layer, they actually did release it as a native port (well, a port of a port, based on the mobile versions).
Whether it’s worth paying for is up to the individual, but I think anyone playing FF9 without using the Moguri Mod is doing themselves a disservice, and to my knowledge it isn’t possible to use it with an emulated version.
Not with two of them, but the Dualsense does have a trackpad.