-kay

Contracts, Contracts, Contracts. I wouldn't play him in the first team, you could move him there for mentoring if you have professional and model citizen players, not because it would hurt his development but because it might increase his reputation making it harder keeping him at your club. Lock him down as long as possible and try do to everything to keep him happy, because soon PSG, Bayern, Real and other big clubs will try to buy him. Unless he's very injury prone he will develop fine, don't worry about it. Check out this video if you want to learn more about training and want to optimize it. But players reach 190+ CA with default schedules. Oh and if you do have to sell to a big club make sure to include a high sell on clause. Personally I feel it's a bit cheaty, but there were some tricks and exploits to prevent transfers in FM21, don't know about fm22, but if you want to keep him at all cost, there are probably ways to do that.

What description? I said it's a hard working role in the current match engine and doesn't match the in game description, never mentioned irl players

That's what an Enganche should be, but that's not what the role does in FM22. Just a quick versus match, milan vs inter, both 4231 same tactic: Diaz played as an Enganche, if you want to can test this for an entire season or so, but I used an Enganche for 2 seasons and this is a typical result. And yes I also thought I could use an old player who can't run anymore, I always had to sub him of and ended up using players with better physicals for that role.

Yes, the anti-trequartista, hard working but 0 flair, it's like Sean Dyche created that role. Despite the description stating it's a stationary role they run a lot and work super hard so I'd recommend more of a BBM type player as an Enganche.

In lower leagues it's often best to mostly rely on free transfers and to max out the wage budget. Hopefully in 2-3 you will be promoted and have a bigger budget to work with.