When having potion of invisibility.
./effect give [player] invisibility 6000 255 true
You can partially see onself (possibly a feature)
but you are invisible when seeing other maps on item frames from other chunks
Image wouldn't attach so here is imgur link.
Please check if that's still an issue for you in the latest 1.15.1 stable release or the latest 1.15.2 (pre-)release.