Yosef is given a very unique beracha –
[בראשית מט:כב]"בן פורת יוסף, בן פורת עלי עין..."
"A son with charm is Yosef, a charming son who catches the eye …"[Bereishis 49:22]
This beracha is not only physical beauty (of which Yosef had in spades) but that he would have charm – or that he would be pleasing in the eyes of his beholder.
How did Yosef merit this ?
The answer is twofold. We may have thought that Yosef is given this because he himself struggles to see the positive in everyone – this would certainly conform to current ideas on charm, in which a charming person is someone who always has a ready compliment or pleasant observation. But this is clearly not the case. Yosef is entrusted with the power of pleasing sight specifically because he has demonstrated an appreciation for the other side, the negative power of sight.
Yosef, at the tender age of six, sees the leering looks that his uncle Esav directs at a beauty like his mother, Rochel, and immediately moves to block him. "That isn't appreciation", he thinks, "that is an appropriation" – it's as if Esav is actually violating that beauty by wanting to possess it. This is a negative application of sight.
The next demonstration of Yosef's sensitivity in this area comes some years later when the wife of Potifar petitions him with her amorous advances. Yosef not only refuses – but realizes that even gazing at her beauty would be a violation of the trust that his master has placed in him.
Hatzlacha !!