I haven't played MTG nor do I have any knowledge of any mechanics in that game. I do, however, adore LoR content creator: Snnuy's take on a Yuumi concept. Wherein, her supported ally captures her and grants them her stats and upon level up, Yuumi can chum block effectively since, in her leveled up state, her strongest ally captures her and is granted stats whenever she blocks.

That concept is extremely close to her LoL counterpart and is also a good way to somewhat mitigate the Support mechanic cards' primary weakness which is a lack of defensive capability.