I have trouble (becuse of limited arm movement) putting on a shirt over my undershirt (for winter!) I need an undeshirt that is as smooth as my skin. The overshirt bunches up on the undershirt as I'm trying to get dressed. The over shirt needs to slide over the undershirt like it does over my skin when I'm not wearing an undershirt.
Other than that Im not sure , you could try under armor tees, it's a brand sports people wear underneath there clothes, but might be to tight for you
Good luck in your search. Hope someone has better answers for you.
https://www.cabelas.com/shop/en/columbia-hike-crewneck-short-sleeve-shirt-for-men
Caveat: the crew neck is high enough that it shows if I wear it under one of my cotton tee shirts.