As a PVE game mode that rewards battle pass exp at the same rate as many other PVP modes, Mercenaries is a good spot for farming exp. However, to take advantage of it, the encounters need to be intentionally prolonged. Otherwise each encounter typically lasts under 2 minutes and a bigger part of botting time is spent in menu and loading without exp rewarded.
Therefore, I wonder if a option to stay still for a certain time during each encounter can be added. Of course, extending encounters slows down coin farming, so it will be a trade off option.