Of course it's cheating, there's no other way to put it. You have unfair advantage, that you created, over anyone else playing regular game with Juventus, or in general.
For example, I had exactly 399 players on trial over 6 years at my club. All of them were free or set for release by other clubs. I had them with one reason - to see their attributes and if they can perform at that level. Many of them rejected my sorry ass and went to league below. While you had 1B transfer budget to begin with.
If you like cheating, do it, but keep it for yourself, do not post your accomplishment in FM thread when you're playing a different game.