I came across this thread by chance, and tried PhotoAcute3 - now no longer developed I think. Anyways, with jpegs it didn't work too well, but with RAW files things went better.
Since it couldn't read GH5 RAW, I had to pretend it was a GH3, and the colours went all wrong. De-saturated and posted her for anyone else wondering if it's worth it.
PhotoAcute makes DNG files that it works with, BTW., so it's not really RAW files, but converted RAW files.
Will now try Affinity, but I believe people have trouble with:
1) Stacking that tries to hide imperfections with blending etc. will for obvious reasons not work
2) Re-sizing needs to maximise variance, so closest neighbour enlargement is crucial
I'll report back any results.
GH5 with Olly 12-40, 1600 ISO 8 exposures hand-held with RAW and jpeg. RAW used in pictures below.