Using the same template in several accounts can be very useful. You can easily copy a template from one account and save it in another by using Visual Code editor.
Steps to copy a template to another account:
Open the templates section and click on the template you want to copy.
Switch to the Visual Code Editor.
Copy the full code and switch to another account.
Now, go to the templates section and import a template using the Visual Code Editor option.
Here you can paste the code and save changes.
You can also check Sharing Campaigns Between Accounts