When I started playing this game, I made this little spreadsheet to help me decide which formation I would use for matches:
Basically, I enter the formation of my opponent by placing a 1 where there is a player. Then I place my players. Below, it will show which team has better coverage on each block. The numbers inbetween are just indicators of how many defenders/midfielders/attackers that I have vs my opponent.
Previously, I could enter the individual player quality on the right side. I removed that for now since I didn't find it useful (It can easily be added back by changing the ACOUNT to SUM in the formulas.
I've been experimenting with the spreadsheet suggesting suitable tactics. They're probably all messed up but it's a work in progress. Use at your own risk.
No, it doesn't guarantee anything, and I make no claims for it. It only helps me visualize the strength of the formations and I figured someone here may find it useful.
I created a throwaway Google account to upload the spreadsheet to incase you just want to try it. Just remember that anyone can edit this one. I recommend you copy it to your own google sheet account and use from there.
Formation Spreadsheet