do you mean where exchanger allow your investor can acces your account?
i think no exchanger do it, but you can use shapeshift.io, decentralzation changer, then you share your Tx id, and your investor can see any transaction or how much your profit.
maybe the OP want is investor send the amount of bitcoin to us and we doing trading for them, and in the end of trading like a week, the profit will be split into two parts, one part is for us, and the other part is for investor. so we doing trading from the investor fund. forgive me if i am wrong.
I think so, or maybe the OP he want make investment in trading account and there are people or broker who manage it for him, and every weeks or months he can take the profit.