Hi @Xine16 ,
In SharePoint online we can add version comments everytime we check out one file then check in. In Power Automate flow, comments function are added in "Check in file" action. You can add "Check out file" action and "Check in file" action in your flow.
If you need further help please start a new discussion via the Microsoft Power Automate Community so that you can get dedicated support. Thanks for your understanding.
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