Microsoft 365's Email service is Outlook/exchange.
there is no direct relationship between that and YouTube. you can't transfer YouTube as far as I know.

do you have any source that says otherwise?

you can take a look at this official support page for changing email address of YouTube:
https://support.google.com/youtube/answer/174100?hl=en

for further instruction you can contact Google/YouTube support and see if they will let you change your YouTube email address and what's the procedure for that. if they do then you should be able to change it to any email address, Outlook, Yahoo, icloud etc.

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