Below is a list of players that have the potential to reach a peak OVR of 90+. Hopefully there is enough information here such that you know where to scout and for what position.
Players aren’t scoutable until their 16, so if a player is listed as 10 years old that means you will not be able to scout for them until you enter season 6 of your manager mode. The potential column is a rough indicator of what their peak value is.
If you are able to scout a player that reaches and overall of 90 or greater without training boosts then please leave a comment with the players details so I can turn this list into an up to date resource.