Here is 3 videos on editing a sent message in teams
https://www.youtube.com/watch?v=BUylzvpHwqIhttps://www.youtube.com/watch?v=t5f1cMei_E4https://www.youtube.com/watch?v=0JgN1Js-Mq0Q. How to edit a sent message in Teams
A. See videos
Q. Does it show message history
A. Editing a sent message only impacts the message being edited. If it is the original message, for example it won't show replies. But editing a message you can still see the historic messages in, for example a Team or Chat
Q. does it bring the edited message down into the most recent activity
A. No
Q. Who can edit a sent message
A. It is a combination. Anyone who has it enabled in the messaging policy in the Teams admin centre as well as someone who is enabled in the Member Permissions of the actual Team Settings
Q. Where to turn on "edit a sent message" in the Microsoft 365 Admin Center
A. Teams Admin Centre > Messaging Policy
Hope that answers your question. To be fair after playing around a bit you'll be able to record your own 5 minute video on it quite easily!
Best, Chris