I've mostly seen cross_speed going for 66B as his ender after a 214x. Not one 66C, and he wasn't even adding 214Bs for more damage since he was going for airtechs anyway. I'd assume this is due to 214x actually just having worse recovery.
Also after most 214Bs mid-combo I see 2B for a relaunch instead of something more conventional from UNiEL, but that's from madu_uma, who is the only other Yuzu player anymore, and he seems new to the game entirely. It's not a name I remember from UNiEL.
Unfortunately Yuzu doesn't have any fancy god-level technicians for UNiST since maa-kun is a traitorous heathen and is riding the Phonon train. It could take some time for things to come out. I can only hope she isn't stuck with lame combo enders like 66B.
What I've noticed most about 236B hurtbox is that if Byakuya has a 623x ground web out and Yuzu does a 236B over it, she'll get snagged and murdered. But I'm chalking that up more to Byakuya just being seemingly asinine in UNiST than Yuzu getting hurtbox changes.