How similar are the British Maximalists and French Sorelians to Mussolinis fascists?

Ive always found the lore in the totalist movements a little confusing.

I presume that because the three groups have relatively close cooperation in game, and their links to historical fascism (all three), that the groups are essentially very similar right?

I don't really remember Mosley or the French Sorelians being nationalists in game though but Im curious if they are or not because that would make them a lot more interesting in the whole dynamic of the third internationale and would explain why they get along on an ideological scale so well.

Obviously if im wrong please say.