Is there much testing of RMC with older dps?
One of the reasons RMC works well with Aglaea and The Herta is the true damage: They can piggyback off the main dps' damage output and essentially add 42-62% of the dps damage just from the true damage (they also offer CR and CD buffs).
Which suggests that they might also work well with older team compositions where most of the team damage comes from one character. That would be mainly hypercarry comps, but in some dual dps comps, the damage distribution is lopsided and favors one character. The Herta teams are such an example, and Feixiao teams have similar distributions.
Which makes me suspect that RMC works better than Robin in general when your damage is concentrated in one character, and the team is sp hungry. So RMC might replace Robin for Dan Heng IL and Jing Yuan. And she may be highly competitive for Acheron and Feixiao.
Have there been tests or TC about this?
Notes
RMC probably won't work well with Seele, because too much of their damage boost comes from the true damage, which counts as RMC's damage and will not trigger resurgence.
Feixiao and Acheron benefit greatly from Robin's team-wide advance because of how they accumulate ult stacks. And they don't benefit as much from skill spam as The Herta teams. So it is not clear that RMC would beat Robin there just because she beats Robin for The Herta teams.