Google Smart Bidding in the form of a target strategy such as ROAS or CPA is not applicable with any other third party bid management, as Google Smart Bidding prevents the possibility of CPC setting when these strategies are activated. Thus, third party bid management systems cannot have any influence.
However, the combination with Google Smart Bidding would be possible in the form of the enhanced CPC, but this would lead to the same disadvantages that would arise with several third-party bid management systems when used simultaneously.