There is so much wrong with the debate surrounding the offer to transfer the Polish MiG-29's to Ukraine it is hard to know where to begin. There are so many questions that are unanswered or that folks don't know from the condition of the the Polish Fulcrums to their compatibility with Ukrainian ones to just how they would be transported to Ukraine, with countless more unanswered questions in between.
To be frank I really don't think there is a much more the Ukrainians can do with a just a squadron or two's worth of very short-legged air defense fighter that is well over 30 years old. They aren't going to gain anything near air superiority over the Russians and they could much better use ground attack aircraft, manned or unmanned, than a fighter with very minimal air to ground capability (if any) on a plane with half the range of a Hornet.
Last but definitely not least that a transfer of fighter jets could possibly trigger an outsized reaction from Russia. As has been exemplified by the inordinate public attention focused on this there is a lot of outsized and disproportionate emotion attached to fighter aircraft and their exploits. In reality the transfer of a mere squadron or two of MiG-29's to Ukraine will likely accomplish very little especially when compared to the massive transfer of thousands of ATGM's and MANPAD's that are actually making a difference in the war.