Team: Kakania (R10 / P0), Marcus (R10 / P0), La Source (Maxed Out), Vila (R10 / P0)
Speaking of "stages blatantly balanced around specific characters", this felt pretty ridiculous to do without Kakania.
These two enemies get a lot of AP and Moxie AND they're immune to Control, so you just have to weather their attacks until they're dead (this is something Kakania helps a lot with).
As for La Source, I needed a backup healer because the enemies always stunned and then ganged up on Vila. La Source can also conveniently block enemy Ultimates even if they're immune to Control. I don't know if this was designed for La Source too, but she sure is convenient.
One other important thing about this fight: both enemies have a specific passive skill you should probably know about. It reads:
"For every 10% difference in HP between self (enemy) and other allies, DMG Dealt +10% and DMG Taken -10%"
tl;dr if you damage one too much the other will hit harder and become much harder to kill. AKA just damage both equally (and also don't die) and you should be fine.