I actually found a great solution to this, if any REAL user is looking for an Answer.
SIGNAL messenger fully supports and export and import menu, with the ability to tick individual contacts discussions.
It doesn't bring the MMS content with it, however there is a great menu to show all MMS content and bulk download that too.
So besides the security reasons to switch to Signal as your default SMS and messaging app, there's some usability features there too!!!Go to the full post