It definitely works that way for Waterfox. LibreWolf has very stringent privacy-focused defaults (like disabling form autofill and purging history and cache on every browser close), so unless you want to manually find all those settings and about:configs you'll be overwriting with a migrated FF profile folder you're kinda defeating the main purpose of using LW over WF. Same for if you were gonna disable the potentially "annoying" privacy defaults in LW.