will the USB connection of the FS3 work on the PS2 (Slim)'s USB ports?
The answer you’re going to get is No. It just won’t work at all.
No. It just won’t work at all.
If you want to get PS2 capability out of your Hori FS3, you’ll need to swap the existing PCB for an MC Cthulhu. Should run you about $30 if you know how to solder and have the tools to do so, closer to $45-50 if you don’t.
If you have the know how, you can dual mod it with a dual shock controllers pcb. Will cost you like $10 unless you already have a spare controller. While its open you should install some arcade parts.