Yes, you can have multiple ConfigMgr Sites in a Domain. Regarding SCOM, you would need to check in the OpsMgr Forums, but as far as I know, you can also have multiple SCOM Installation in a Domain.
fyi, there is no ConfigMgr 2016, the latest Version is called current branch.
Simon Dettling | msitproblog.com |
@SimonDettling