Sometimes when you are battling a random team while walking around the region, after you have successfully beaten the team, one of the members of that team may ask for you to recruit them.
Note: You can't scout two people at the same time, resulting in you wasting the Nekketsu points. Some require a four-person lineup match or matches that you have to win consecutively in order to scout the specified character. Players are recruited by going to a certain location, and then talking to them. You have to pay the machine to scout, with the Nekketsu points you obtain from winning stray soccer matches.
The tree starts with Endou Mamoru, then extends to a branch or multiple branches of other players, and so on. The scouting tree is a tree of miscellaneous players that you can recruit players that are normally scouted from stray soccer matches or random encounters. Through that way you have to pay the machine to scout, with the Nekketsu (Prestige) points you obtain from winning stray soccer matches.
The machine refreshes the list of players to scout every time you use it. There are scouting machines planted in the Inazuma Eleven games, that list the current players available for you to scout from the teams you played against so far in routes.