After purchasing this battery I can confirm that it is compatible with the mark R6 II.

Batterie au lithium-ion rechargeable LP-E6NH (incluse)/LP-E6N
https://fr.canon.ch/cameras...
Donc Oui

battery works fine with my r6 ii!

Unfortunately I can't give you a 100% guarantee if it's compatible, as I have the Canon R6. Check on the web (search engine with keywords R6 Mark II ect.) if this battery is ok for your camera.

This battery works with the Canon R7 as well as the Canon R6.

I use the R6 Mark I.
So unfortunately I cannot answer the question.