Not so easy. Poland's Mig29's have been integrated into NATO standards, electronic plugs, hardpoints, control etc. They will have tp be rolled back to Russian missiles and hardpoints with electronics. Then do they have enough Russian missiles - Russia will not ship them.
If they also gets lots of NATO missiles, they can operate in Ukraine as long as missiles are supplied. The planes must be painted, easy enough, or they will be NATO planes with NATO missiles attacking Russia = a flash point.
Recent events indicate a possible step back from the brink happened today?
I don't think these will ever make it to Ukraine. However if the US promised Poland US jets as a replacement this may have been a nice quick way to get some new expensive hardware for free.
I would think hundreds of cheaper drones would be more useful.
In addition to reconnaissance, there’s a lot of artillery, vehicles, etc. they could directly or indirectly target