160xp I think VM is estimating him too low right?

https://www.virtualmanager.com/players/17329494-marlon-mc-buck/training

Also does anyone know how I'm meant to know if he is formidable or promising etc? Is there a plug-in? Am I meant to hire a scout? Or do I have to keep checking the graphs?

You need a scout first, then go onto your club profile and in the bottom left corner it says 'evaluate players' takes 3mins

Considering he only has the 2 trains above his average which are skewing his long term average, I would say VM has him priced appropriately, maybe 100k low if I was being super nitpicky, but in the general zone for his potential. This player is probably in the “ok” to “below average” range for potential, so he’s definitely not going to simply jump into the millions because of one train.

As for a scout, you will need one that has 20 in potential assessment, if you want one that can find untrained youths as well, you will need 18-20 in management and discipline on top of the 20 in potential assessment. Management and discipline have an impact on how many youths he will return with when sent out to scout a country for whatever settings you establish, and the possibility of finding an untrained in that report. Finding untrained youths in these reports is not guaranteed, but it becomes possible with the high management and discipline values of the scout. Ideally you want 20 in both categories, but finding that may be more difficult than just a 20 in the potential assessment.