So, technically they're war-time entertainers and their mechs are basically standard-bearers. And they also double up as a way to call enemy commander's mechs to "champion combat" as in Robojox?
To avoid irl parallels(because I can't recall names of bands and singers, who performed near frontlines during WWII), let's give them an analogue to Redeemer warmech of Brotherhood of Nod. Exept in this case it's just inspiring troops and getting attention of enemies, not using literal mind control on allies and enemies alike:D
The big bots have some very Evangelion-looking heads. That's not a criticism, it's just a design choice I'm noticing, and I'm finding it kind of primes me to expect a lot of physical and psychological trauma, and maybe some light body horror.