Just to share-
Here are 2 players who have played out of position every match for many seasons. I bought both dual position players essentially as back ups for my 4411 set up, so they could fill either the defensive or mid flank position (usually 4411 attacking, mixed, mixed, sometimes counter; zonal, normal, high, off). Instead, both became starters in the ML and MR positions for most of 4+ seasons.
Stanton had playmaker SA when purchased, Milovanovic was trained with CK specialty last season. I never bothered to add a 3rd position (the midfield position they always play) because from day 1 there never seemed a need. First season they were fairly high Q for my competitions, then became more average. Both have always scored and assisted, and ratings have been consistent every season. (Last season Stanton had a hat trick in first match of both Cup and CL)
I don't know if they or the team would have done better playing in proper positions. I never saw anything clearly indicating a problem, ratings good, majority win rate, passing completion could hit 90+, they rarely fouled, and opposing wings didn't obviously perform better.