Primarily rigging/blueprint work as the mech model/skeleton already exists, which I will provide:
The game is multiplayer, so the code needs to be properly replicated and optimized. The first priority is to make the arms follow the movement of the motion controllers (sort of like Evangelion) and have hands open/close from trigger-press. Stretch goal would be to have a copy of this controlled by an AI for single-player or co-op vs computer play.
If interested, please send previous work samples and proposed price to email@example.com. Fixed price preferred, and you will be free to keep rights for re-use / re-sale in asset store.