We also use the same term overseas hence the term "seas" lol. And I get what you mean that they can cross border Myanmar/Cambodia/Laos to get another 90 days.
What country are you moving to? I have never encountered anything like this unless you are applying for a residency or setting up a self employed business to another country but the police clearance should come from your home country not Thailand. If you are just simply relocating, declare your home country instead.