Thanks for checking it out! A Teams integration is definitely in the backlog, but I should probably bump it up now that you mention it. The average Jira-using scrum team is probably also pretty likely to be a Teams user.
The average Microsoft office corporation gets Teams free and most those corps are just learning Agile so they are willing to buy, I think.
Standuply and Geekbot are the 2 I see. Maybe Teaminal will be there also.