Since it is unlikely we'll ever get a Man O' War as a player ship, I thought why not make it a naval world boss for Adventure mode? This world event would be harder than any other world event and would grant great rewards if you manage to kill it. The more in-depth specifics on it, such as where/how it would appear and how the world event and the boss itself would work, is still up for debate, although a few pages could be taken from the Tall Tale naval boss battles, but what do you guys think about the idea of it?
There are a bunch of other posts regarding this topic (most quite old). Still, I'd love this idea to be implemented. Here are a few other posts on the same topic:
https://www.seaofthieves.com/community/forums/topic/136834/proposal-for-season-4-or-season-5
https://www.seaofthieves.com/community/forums/topic/123530/man-o-war-the-mobile-skeleton-fort
https://www.seaofthieves.com/community/forums/topic/53304/man-o-war-public-event
https://www.seaofthieves.com/community/forums/topic/131467/trading-company-man-o-wars-emergent-encounter
https://www.seaofthieves.com/community/forums/topic/137240/a-possible-way-to-introduce-the-man-o-war-as-a-world-event
https://www.seaofthieves.com/community/forums/topic/143404/content-suggestion-new-pve-boss-fight-huge-skeleton-ship-man-o-war