Hello. This looks like the problem that occurs on M1 (or M2) Macs that can be resolved by setting the applications to “Open using Rosetta” – see Define not showing photos correctly where I explain how to change it.
I installed Nik 6 a couple of weeks ago, and the two Sharpener apps still need to be set to “Open using Rosetta” on my Mac mini M1. However, DxO says these apps are being rewritten (see https://support.dxo.com/hc/en-us/articles/4850799977501-What-are-the-new-features-) for release later this summer. So after that, Rosetta emulation will likely no longer be required.