I’ve used Hugin a lot over the years for panoramas, and I’m told it will also do a good job of focus-stacking, although I’ve never followed the extensive instructions on how to get it to do that.
I’ve had a couple of times(out of hundreds, I guess) where Hugin didn’t like some aspect or other of my images, and yielded unpredictable results. For example a 5-image panorama of our archery target range was processed to have a nasty bend on the far left by Hugin. My daughter’s copy of Affinity Photo gave an image that had the correct perspective.
I now use paid software routinely for image stitching.
I followed a number of tutorials on focus stacking in GIMP, and though tedious, it’s possible to get some excellent results. (Example in mono.)
G’mic does a fine job of aligning the images.
I’ve also found that working with a mouse (to focus-stack in GIMP) is not a pleasurable process. I use a graphics tablet - I have a wireless “Ugee” brand that works an absolute treat in windows and Linux. It cost me about AUD$80 during the last November sale on AliExpress.