again not foss so won’t dwell at length — but i use fund manager from beiley software. commercial, but works double-entry and handles more investment complexity than a human could ever need. windows app, i run it under wine on linux and crossover on mac. (i don’t own a windows box — that’s how irreplaceable it was for me.)
i rather doubt a government would push people out of signal-protocol apps and into Some Other App if they didn’t already have a backdoor into the designated substitute