Correction to my last post
I made a mistake in this post, I assumed that with the new buffs, Cyno could activate the 3 stellar superconduct hits with just the elemental skill, but re-reading the buffs I noticed that it says this:
"While in the Pactsworn Pathclearer state of Sacred Rite: Wolf’s Swiftness, Cyno will periodically enter the Endseer Stance state."
Secret Rite: Wolf's Swiftness is the name of the elemental burst, so the only way to actibate the Endseer Stance is by using the burst, meaning 2 things. First of all, you need ER to activate the burst (and remember his modest cost of 80), and secondly, he needs to be on field at least 8s (in burst) to activate the stellar hits twice making more difficult for Sandrone to retain Diona's and Beidou's buffs.
I've been trying to calc how much ER you'd need for this to work and if you use Fav on Beidou and Diona you'd need around 130ER and Sandrone would have 4s with all the buffs, so this could work depending on how Sandrone deals her DMG. If she can deal all her DMG in 4s this could be great, if not my dream team is probably wrong
You could hit just one instance of stellar hits with him, but that'd make you need more ER and it'd be difficult to deal with Diona's and Beidou's 20s cooldowns.
But well, we still don't know exactly how much time Sandrone is in field, so maybe there is another way or another character to fit in the team. Sorry for my mistake
I hope I'm wrong and you can enter de Endseer Stance but I think it does jot seem probable