Could you add a second guard when working with incompatible units?

[Egg Centric]

I see threads like this one where the systems of multiple units won't play nicely with one another and wonder if - particularly during the covid timetable where there's presumably extra staff - a way around it might be to have two guards on the service, one in each incompatible unit.

Both guards would be responsible for announcements and so on, and the one in the rear (usually - might depend on station etc) could be responsible for doors, safety of the line, etc. Could this work?

 

[Energy]

Still the problem of driving the unit and providing power for it. I also can't see this being too much of a problem for most operators, even at Northern there are only 2 groups of incompatable DMUs (170s and Sprinters can work together) although the 331s, 333s and 323s aren't compatable.