Every choice field value has a related number. So, if you know the number of the value you can set it dynamically.
What you could do is add a dropdown list of your choice options to your trigger action. In that list you can match the numbers from your choice field options by putting the correct numbers in front of the label.
Below is an example of that approach.
In the dataverse field you could use the expression instead of the dynamic content field.
That expression will return the first character of the option. In the case of '3. Microsoft Teams' that will be '3'. If your options are longer numbers you have the change the length of the substring function.