I'v find how to fix pregnancy images issue.
In file "mods\expanded_portraits\exp_ch_stats.gd" in function "func is_visibly_pregnant():" need to replace:
--- return has_status('pregnant') or has_status('heavily_pregnant') +++ return parent.get_ref().has_status('pregnant') or parent.get_ref().has_status('heavily_pregnant')
Not sure why "parent" should be called. Just copied that calling from "src\character\ch_stats.gd" (line 1738) from original game code.