There is a game from 2018 called Empires Apart which has lots of similar design in AOE2 , and lots creative design before AOE4(like Mongols can pack up buildings,etc).
In Empires Apart provide a hot key which let players select wonded units among selected,as the follow pics
I can simply press ‘V’ to select wonded units among selected. Which should also aply in AOE4 .
AOE4 get lots of healing methods compared with AOE2,but its harder to pick wonded units from the folded units list to go back home to get heal.
I think add a hotkey to select wonded units will give monks higher priority , and more diversity to this game