As most people know, after the v4 changes, TCs discovered that you are better off using Nicole last in the rotation to get TTDS and all the quills on Varka, rather than using Prune last.
Thanks to hitlag extension (and after some testing on the dummy), people figured out that you can get about 78% uptime on VV's debuff and basically full uptime on TTDS for Varka's combo.
Because of this and Nicole's high ER requirements, most people are recommending using Fav on Prune and TTDS on Nicole, even over 5-star options (unless you pull for Nicole's signature).
But I'm not sure if this is really the case.
Using double Skyward Atlas as an example (which I assume most people have one or two copies of lying around), you can easily get the full buff for both Nicole and Prune. At least according to my calcs, this is better damage-wise than using Fav + TTDS. (And these calcs assume Durin is getting the full buff from Nicole even on the first rotation, which he is not.)
The problem is, using KQM stat distribution, you are one ER roll short of reaching the 191% ER recommended for Nicole with no Fav weapons on the team.
But I really think this should be way more consistent than balancing ATK and crit rate rolls on Prune. Getting a bigger shield is also a plus.
I'm not really a TC, so I would really appreciate any thoughts on this.
TL;DR: Skyward good, but not KQM compatible.
*Edit: Updated some numbers (lower ER requirements on Durin with Fav).