we can read "I don't think IMAP has the concept of move."
It is correct that IMAP RFC2060 does not provide a 'move' functionality.
However there is a RFC that proposes a MOVE command:
Internet Message Access Protocol (IMAP) - MOVE Extension
I see that some other IMAP mail servers support it e.g. Dovecot:
Could we please investigate the opportunity of implementing this, in particular to have cleaner Moves.
I an not sure also what client already support this:
it seems Thunderbird does:
but a search for +Outlook +"RFC 6851" did not give a clear answer if Outlook supports this or not yet.