Doubt about the formations in the editor

[Gastofm]

Hi. I am reformulating DT's line-ups in the top five leagues in Europe. And I thought about canceling all the preferences of the technicians without a club, so when they arrive at a club they have a certain alignment. The theme is the following, I know that the preferred formations are generated, but the offensive / defensive ones too? And another question regarding the offensive / defensive formations, if they are canceled from before, if new ones are generated, can those DTs use them before the game, or is it only when they have to win or lose it?