Most underrated footballers
I'd say it's very subjective, so really I think you're free to suggest anyone Mystik if you think they're underrated. I kind of agree on Alaba, his versatility is often useful, but he's not one of the Bayern stars, so gets overlooked by fans. Not sure I consider him world class, but I think he's a very good player.

Not sure I really agree with mzk's list, I don't think any of them were particularly underrated (Morientes was often in Raul's shadow I guess). Also Lampard better than Zidane, Xavi, Seedorf and Pirlo?  Dodgy

I think Insigne's underrated a lot of the time. This season in particular he's been outstanding but is often in Higuain's shadow. It's amazing he's not really a bigger part of the Italy side.

Bonaventura's another I'd add to the list, his performances last season and especially this really deserve much more recognition than he often gets.

Finally, I'd suggest Acerbi. He's often considered a mediocre defender by many fans, especially Milan fans for his time here. However, while he's not a top class defender, he has been a very good defender at both Chievo and Sassuolo, even with his difficulties with cancer.
For Most fans I know, Alaba is a star at Bayern and is pretty much well known.

A lot of good players from Serie A like Insigne and Bonaventura are underrated - mostly coz the fans of other leagues do not know of them. Considering how non popular Serie A is now that is not a surprise. Even Niang is better known that Bonaventura outside of Italy. But that's probably coz of Arsenal's interest in him and anyone they are interested in gets a lot of media coverage.

One underrated player I'd say was Gattuso. Even today, for many fans, he's nothing more than the guy who fought a lot and had a temper. and I don't think it was till WC 2006 till people realised what a crucial part of the midfield he was. Considering he came from Salernitana, the guy certainly did a great job with his career.

I can't even imagine the reception he must have got in those days coming from a small team, especially at that time we had a lot of buying power. Some fans must have surely been baffled.