Pillow It!
Does this add-on do automatic retopology for game engines?
No, the topology is always defined by the user. This tool is a fast workflow generator that inflates and stitches your existing mesh based on your marked seams. If the "Physical Seams" setting is turned off, then the seams will not be separated, keeping the topology clean.
Can the settings be changed after running the operation?
Only some can. For example the subdivision amount, pressure, materials and fuzz amount