The Bolton Army under Ramsay's command from the Battle of the Bastards takes on the Dothraki horde from season 7 that fought the Lannisters. Assume equal numbers for this battle. Otherwise, it is an all-out fight until either side is completely destroyed.
It’s been talked about in the books,that the Dothraki’s are only dangerous if you’re stupid enough to fight them in open warfare. The second you take their mobility, you already break them in half.
Not only that, they wear no armor. That’s also another point to have. Where as the North, though there armors are not as defensive as their southern counterparts, stills carries armor.
The Dothraki have no lances, pretty sure Ramsay’s army had lances in their Calvary unit.
The Dothraki have no sense of planning, all they do is charge and overwhelmed, any Northern leader could outthink them.
In the end, season 7 Dothraki had surprise and confusions on there sides, plus a giant dragon that was burning the Lannisters.