I had this idea for a while now, and I was curious if people knew of any existing novels that tried go down this path. Basically, rather than an MC is OP with a lot of powers and everything, the MC is extremely weak and their only ability is to "play support" and grant buffs to other people. The story would be about how the MC has to take a different approach to life than the MC would otherwise be used to.
Boku wa Isekai de Fuyo Mahou to Shoukan Mahou wo Tenbin ni Kakeru He himself is weak but he has support abilities to compensate.
Kamigoroshi no Eiyuu to Nanatsu no Seiyaku Mc can be OP but the power need several conditions to activate, leaving him as the weakest among the seven hero normally
Hmm... She's not quite support but you might want to check Worm. It's set in a modern world with superpowers, and the MC has the power of controlling bugs. Most fights are team fights, and she usually does not take the main DPS role. She's more in charge of crowd control, scouting, distractions, etc. Oh! Also maybe Kono Subarashii Sekai ni Shukufuku o! The MC is in an OP team full of baka, and he's ok but has trash stats except for luck. He's more of an "all-rounder" with sword, bow and magic, but he'r really there to cover up for his teammate's lackings (i.e. supporting them).
Please make your reading list public, helps a bunch. I’ll Live My Second Life! - MC is pretty weak and mostly support. I Reincarnated Into a Vending Machine - Well, when you are a vending machine, support is pretty much what you do! He can't even move without help of others.