For telemed, the biggest restrictions to this will be in the form of state licensing laws, malpractice policies, and international laws, but yes it is very doable. Also important to keep in mind payment of taxes and what is involved, because in some countries and states you might be charged twice for those. I know a handful of people who do just telemed from out of the country, but in many cases they have special malpractice plans for this.
When you get closer to the time of actually doing this and know more details (i.e. your home state, the country you'll be mostly living in, etc.) you can get more details and specifics about what you need to do and the cost of things to determine if it's worth it to you.
As for actually working abroad and treating patients abroad, that is another story. Basically the only way to do this without individual country licensure which may or may not require specialized work visas or national residency, would be to work for an aid organization (e.g. MSF) of some kind in which case you would work based on maintaining individual licensure in your home country.
You could also try working in a country that has reciprocal licensing programs with the US/ABFM (e.g. New Zealand locums) as this process of licensure in that country is easier.
In many of these cases you'll be working for the same if not less than you would make with any job here, because what you give up in salary you gain in being able to work how you want.
In all honesty, you might be better off doing locums and just taking prolonged trips abroad (like months at a time). But it's really up to you based on what you would want.