Add the From field on the action “Send Approval email” like the "Send email" Action
You can now customize who the Approval appears from - read more here: https://flow.microsoft.com/blog/button-types-more/
@Laskewitz I saw the example by @Sunay but the customer wants to use the Approve / Reject buttons in the email (Adaptive Card). Is there some way to do this?
@rajpamamull No there's no way to change that. The only way to do that is to create your own adaptive card and send that separately as @Sunay said in his comment. I can imagine your client wants that without the steps Sunay explained in his comment, but it is seriously not a good idea. If they would implement this, everyone would be able to send an approval email as someone else. How would the CEO of your client feel when everyone is sending approval requests out of his name? That's not something he would want.
I have multiple clients who I explained the same thing, and they don't mind this solution. So maybe it's a good idea to talk to your client and explain this. I'm sure they'll understand if you explain the security risk.
Having read @Sunay comment I have to agree with the logic and feel this will be easy to explain to clients.
The customer is asking for the From address to be a designated address such as firstname.lastname@example.org. Not a runtime configurable From address - this would clearly be bad. If it could work like the O365 Outlook send email action where a connection to the From email account can be setup (requires authentication) by the workflow owner/developer this would suit or something similar
I just added a video to my YouTube channel where I send an approval via a shared mailbox instead of the Microsoft Flow standard email address. I hope in the future we can also add the actionable message to the email, but for now, we'll have to do with a simple email.