Chuck Todd mentioned on Meet the Press a few days ago that his pet theory is that Biden will commute Trump’s [federal] sentence if Biden gets reelected (obviously, Trump pardons himself if Trump is elected). As much as I would hope that wouldn’t be the case (honestly I’ve been convinced jail time is inevitable for Trump on these charges and this evidence), I think it’s pretty plausible this winds up being the conclusion to this whole saga.
I would think of it less as “what could Trump give Biden” and more of “what could the MAGAs in Congress give Biden.” Chances are good that a second-term Biden will need to work with at least one Republican-controlled chamber in Congress, and something like this might be what allows him to do something as simple as pass a budget.
For better orfor worse, Trump is almost literally the second coming of Jesus to a large number of Republicans, and commuting his sentence might be something that provides Biden some leverage that could allow his presidency to function. Again, not saying that’s anywhere near an ideal outcome (I’d much rather see Trump rot in prison), but it wasn’t an outcome I’d previously considered and one I could see happening.