We scuba dive, so we get DAN (Divers Alert Network) insurance to cover diving medical and because most places require you have dive insurance.

They also have trip insurance on a per trip and per year basis that covers also medical as well as travel.

I don't think you have to be a diver to join, although I would call them to be sure. We do a lot of travel and our US based insurance doesn't cover us in another country, so we get the yearly coverage. They don't ask about pre existing conditions.
https://dan.org/membership-insurance/membership/membership-faqs/