Hello! Almost full list of Implants is available here (excluding some novelties)

Thanks for speedy response but those are just the shop ones aka the rubbish legendaries. I was wondering whether there was a grav beam implosion time that exists in the game. 

There were no releases of new Implants for Graviton Beam recently. I think you may meet a Mech with a ranked-up Weapon, Implants, and Pilot. However, if you face such an issue again, please share some screens or video recordings to clarify this

Gravaton beams have a smaller implosion time of there are two of them and also if that are leveled up more.

Smaller implosion time for 2 grav Beams? Not read that anywhere. I thought they operated independently.