There are multiple variations of this style team simply by altering the speeds slightly.  The ranges on this particular tune are very tight, so make sure to double check (both on affinity and off).

UNM

If using Sepulcher Sentinel (or equivalent 4 turn cd block debuff champion) you’ll want to delay 1 turn (a1, a2) so the block debuff happens on the second attack of her double attack skill (right before the 2nd aoe)
The other 4:3 champion will take a double turn after the stun and before valkyrie on void and before the stun on affinity.
The 185 champion will go after valkyrie on affinity.
Recommend delaying valkyries a2 skill two turns (a1, a1, a2) so it activates before the first aoe.
You’ll want to ensure everyone has increase defense before the stun or the other 4:3 champion will take the stun on affinity when the increase defense buff from Sepulcher Sentinel falls off.

Nightmare

If using Sepulcher Sentinel (or equivalent 4 turn cd block debuff champion) you’ll want to delay 2 turns (a1, a1, a2) so the block debuff happens right before the 2nd aoe.  She will take her double turn after the stun.
The other 4:3 champion will take a double turn between the aoe’s.
Recommend no delay on valkyries a2 skill so it activates before the first aoe.
You’ll want to ensure everyone has increase defense before the stun or the other 4:3 champion will take the stun on affinity when the increase defense buff from Sepulcher Sentinel falls off

It will be near impossible to keep increase defense up for the full fight, but you should be able to still get great results and last a LONG time with this setup.