Thanks for sharing these, Pedrito. Hope to see more and looking forward to trying them out.
You could edit the tactics before a match using a second controller for the CPU team, then kickoff and switch that team back to CPU control. This is best for changing a team once you're in career mode, although it will deactivate trophies (if you care and not that there are many for offline play anyway).
Ideally, you save a custom squad with the formation/tactics edits and use that squad file when starting your CM. Just be sure to always save a backup file or two because FIFA likes to overwrite files when you download updates needed for online modes.