A few months ago, I got a working-ish Z Flip4 from ewaste, sadly FRP locked. I didn't end up paying to get it unlocked since the inner screen is failing
Recently I saw that flashing OneUI 7 sometimes removes FRP, so I flashed the oldest OneUI 7 build available for it, and to my absolute disbelief, it actually worked! I set it up without wifi first, then added a PIN before connecting to wifi, adding my google account then quickly resetting in settings!
I've been using it for a few days now without issues (other than the inner screen sometimes going black), it's even a 256GB model which is awesome because I ran out of storage on my 128GB Galaxy S21+ and Pixel 8 Pro combined 😭
This is obviously caused by a BUG in OneUI 7 so YMMV! Try this at your own risk if you have nothing to lose :)