Come on now, SHELL?! It's not the best possible noun to use as a name. There are flower names, jewel names, and all sorts of nature names and other nouns that sound far better as names. At least spell it ''Chelle''. It would be better to name the girl Michelle and call her Shell. I can't see this on a guy.
Also, this name can also be a Masculine name as possibly a diminutive of Sheldon and Shelby, making this name Unisex.
https://www.behindthename.com/name/sheldon
https://www.behindthename.com/name/shelby
https://forebears.io/x/forenames/shell
According to the USA Social Security Administration, 16 boys and 15 girls were recorded with the name Shell in 1963.
https://www.nancy.cc/baby-name/shell
https://www.names.org/n/shell/about
A real male bearer of this name is a Canadian radio and television personality and home improvement expert: Shell Busey.
A fictional male bearer of this name is Shell Scott.
https://en.wikipedia.org/wiki/Shell_Scott
https://en.wikipedia.org/wiki/Shell_Busey