After Thunderbird Import: Migrate IMAP account to Exchange account

I just installed eM Client and imported a Thunderbird IMAP account which worked well so far.
Since the Mailserver is an Exchange Server i would like to change the account type from IMAP to Exchange, which was not directly supported by Thunderbird.
How can i do this?

I solved the problem by just creating a new Exchange account instead of importing IMAP from Thunderbird. Just had to move mails to differently named default folders.

the setup cannot be changed from IMAP to Exchange directly, it is indeed needed to set up the account anew.
Glad to hear your issue has been resolved.