to upload stats, go to the card page on real, on the top of the screen theres a button that says "stats" click that, and take a screenshot (take as many as you want) and submit below, if you dont know where to go or what the stats page should look like, expand the screenshots below, if theres players you dont want to sell select them or just ignore the options of people buying them
On the card page, tap "Stats" at the top. Tap the image for full size.
This is what the stats page looks like — screenshot this list.
Reads the player names off your screenshots and shows the highest standing offer for each, in the sport you have selected.