It processed a few seconds but then nothing happened.
The ML denoise option is also not checked after i have chosen it.
When i do the same thing with the ML enhance option you can clearly see a difference and it is checked after selecting it.

2019-10-10 19:31:56
2019-10-11 09:34:39
2019-10-11 11:22:47
2019-10-14 11:02:02
2019-10-14 12:16:11
If you could share a sample or two with us at support@pixelmator.com, we'd add them to our dataset and check why the noise isn't being removed. As for ML Denoise not appearing in the Color Adjustments pane, that's actually by design as it doesn't currently have any sliders and can be applied repeatedly. We'll do our best to make some improvements here, though.
2019-10-20 09:42:31
2019-11-28 14:37:37
2019-12-02 15:48:27
Improvements are on the way. They may take a little while but some other great new features should bring some joy in the meantime.