Over half of our alumni medical missionaries are DOs and they serve in a multitude of countries. There are some nations that incorrectly categorize a DO as a chiropractor and so those do not work for a DO If you have a specific country in mind, do a web search for that. Here is a link that has some information though it may not be up to date:
List of countries where US-trained osteopaths are recognized.
Answer from John McVay with In His Image Medical Missions.
“Christian Academy of African Physicians Board Member”
If your country of interest is not yet granting unrestricted practice for a DO, the AOA desires to engage with your assistance and local “champions” to make a way forward.