Rather than an Action which would require the system knowing which Record ID# to edit, I suggest a different approach. I suggest making a summary maximum of the [Record ID#] of the revisions and then look that up down to the Revisions.
Then you can have a formula which calculates if the revision [Record ID#] = the most recent (Highest) Revision [Record ID#].
There are enhancements on that technique if you like to mark Revisions as Valid in case you need to roll back and disqualify a recently loaded Revisions. In that case the system would take the highest [Record ID#] of valid Revisions in that Summary Maximum field.