If it is a basic, operator-led model, then you do not need anything. If you are going for a regulatory approval-based relationship, i.e. EMD or RA, then you would need a law firm and a compliance program, etc. The sponsoring institution can recommend such names, we do not get involved and there are no additional costs from our side.
What sort of sponsorship are you seeking? Operator Led, EMD or RA? (See https://faisalkhan.com/delegate-status-comparison-table/)