He’s not pacey though. All the examples of his play in the videos shows a player who is technically good but to succeed in the PL as a winger you need pace. Ounas isn’t the type of winger to make a penetrating run in behind he is more aloof a carrier with defenders in front of him.
Mane
Salah
Sterling
Fraser
Son
Sane
Zaha
All have pace.
The only player of similar speed to Ounas is Hazard (but he looks quicker and is far greater technically).
I really don’t think he’s the answer to what we need.
I really don't think Zaha, Fraser, Salah speed of dribbling around the opponent are as great as that of Ounas. And that's one of the reason they tend to lose the ball often because they tend to slow down whenever they try to manoeuvre their ways past the opponent which helps to give the opponent enough time to catch on them in comparison to the likes of Hazard, Ribery, Mahrez and even Mane/Son/Sterling/Sane (although Mane/Son/Sterling/Sane have better speed than the aforementioned) who have got high speed at which they run at defenders and not just running into space like Sanchez, Zaha, Salah seems to love doing.
I really don't fancy the kick and run style of some of the wingers you made mention of. Personally, I think the hallmarks of a winger lies in his quickness (acceleration) to evade defenders coupled with his agility to easily change his direction while running on the ball and this helps to confuse defenders and open up more space to operate as well as the speed at which he dribbles. In a much lesser space like a possession based style/against a team that park the bus, a winger won't have the space to operate even if he's an Usain bolt hence he will have to constantly rely on his acceleration, agility, dribbling speed and quality techniques of course. All these I find in Ounas. If you watched the clip above, you would realise, his opponent were parking the bus most of the time he was against them.
His speed looks great also. For example, the Benin match, where they have to constantly hack him down because they couldn't contain his speed. Or the AC Milan match at 1.53 of the clip where a Milan player who already started his run in front of Ounas couldn't meet up after Ounas went past him. Juve players couldn't contain him as well despite the little spaces left on the field of play. And I also saw him against Arsenal, albeit for few mins but Arsenal players were forced back as soon as he was on the pitch yet he still had his way past them. I think he was the only Napoli's forward that made an attempted shot on goal. Anyway, I wouldn't mind to have him on a loan with an option to sign permanently.
Also Sancho for example, doesn't have the enormous speed of the aforementioned players nor is his dribling speed as great but his acceleration, agility and techniques are fantastic hence he had no difficulty going past defenders when compared to someone like Depay who doesn't have the acceleration, agility nor the dribble speed to manoeuvre around defenders. He has to depend on the amount of space given to him whenever a counter attacking situation comes up and even at that, he doesn't have the speed to constantly exploit it unlike Salah, Zaha, Fraser hence why he's better deployed through the middle.