Do y'all have some manwha there with a big man? Like not the bulk one but the chubby one? ...

Hardly in the most cases they lose weight or somehow get „handsome“ if it’s not the ideal in the beginning.

As you did not specify the genre I drop some things you might be interested in.

Here is the chubby Tag list:
https://www.mangago.zone/tag/chubby/?page=1

In those they are quite sturdy and don’t change, BL

https://www.mangago.zone/read-manga/bongchon_bride/

https://www.mangago.zone/read-manga/tractor_full_of_love/

https://www.mangago.zone/read-manga/my_pudgy_co_worker_is_a_snack/

This one is sturdy chubby and gets bulky, SMUT

https://www.mangago.zone/read-manga/sex_exercise/

This one is not manhwa but chubby husband and stays like that, super recommend, FANTASY ROMANCE

https://www.mangago.zone/read-manga/the_flowery_path_of_evil/

And in this one he is sturdy and has lotta scars etc stays also like that, FANTASY ROMANCE

https://www.mangago.zone/read-manga/another_typical_fantasy_romance/