There's a huge difference between playing in a position and excelling in it.
Could Ronaldo play central midfield? Yeah probably. Would he be any good at it? No he'd be useless. Could Kompany play up front? Yeah probably. Would he actually score as many goals up front as say Aguero? Of course he wouldn't
Jeez some of the stuff you come out with
Because I said Aguero and Kompany should switch, didn't i, well done.
Actually I pointed out players generally speaking suit certain roles, but don't bother reading that part. An attacking player that is great in every aspect of attacking, can play every attacking role, its as simple as that.
That is why Aguero has played from wide and from upfront, and he has played in different ways, taking the ball to goal on his own isolated(and been excellent) held it up waiting for support, and playing from wide providing that support very well.
As for if a player can excel in any position, yes that is the point, the best players CAN, that is why Messi is awesome from either wing or starting as a striker, or playing from behind a striker in the middle. Fabregas looks great wide, upfront, any position in central midfield, he excelled in all of those roles. He just won his third international tournament, Fabregas got his 3rd assist in a final, 3 in a row, playing in a completely different position, in which he was completely excellent and before this season hasn't played as a striker properly before.
Kompany, was the worst example you could have come up with because I've seen him play fullback, play in midfield excellently and was considered more of a DM when he was bought and started at City mostly in midfield. He's very versatile, and looks pretty damn good when he runs forwards, and scores good goals. That's the point, he's MORE suited to a defensive role and he excels in ALL defensive roles, but he's still pretty good when he does run forwards.
If one player is the worlds best at right wing, and a not as good but brilliant central midfielder, and another player sucks in the middle and is very good on the right but not as good as the first guy, where do you play both?
Firstly you don't know that Moura is best on the wing, because he might become better elsewhere, secondly he might already be a much better central midfielder but in the team he plays in, the TEAM is better with him playing wide.
This is the point, most great players can indeed play most roles, most players pick defence/offence pretty early on and specialise.
As I pointed out, almost everyone in your offence can play in multiple roles, and HAVE played in multiple roles. Carrick, who has been essentially a sitting/holding midfield for years at Utd, joined Utd as an attacking creative central midfielder.
If Moura can be a better central midfielder than you can buy, and you lack central midfielders, he'd still be a massive improvement to your weakest area on the team, buying the worlds best winger to replace the second best winger in the world wouldn't improve any team much at all.
Lastly, if Ronaldo played in central midfield, he'd be brilliant at it, you know why, because he's a brilliant player. Remember how no one thought Beckham could play in central midfield, then he made it his new position and won titles playing there?