Who should i drop to get Scheffler of the IR?

I think you drop Scheffler. You really only need him on the Charger's bye week, and I really don't think skipping the TE position for one week will hurt you. I think you can leave Scheffler at the IR position indefinitely in most leagues, but must drop a player to get him into the starting rotation, which if that is the case, delay until the Charger's bye week to make a decision.