There's almost going to have to eventually be some type of recompense situation.
If a kid from school A enters the portal and signs with school B for 200K, then school B should be required to repay a like amount (or %) of that NIL contract to the school the kid transferred from.
I know it sounds barbaric, but, if they are going to treat it like free agency, then the team losing the player should be compensated.
This is a complete can of worms and like Dingle says, it likely happening all over the country.