Integrating explicitly nazi paramilitaries, not only Azov but also Right Sector and a group literally called Freikorps into your military makes you a state sponsor of nazism. These are groups which before the war provided training to fascists from the US and Western Europe and harassed and intimidated people attending pride events. Far from a handful of nazi fellow travelers scattered across different battalions, these are ideologically committed terrorist groups who now have unlimited access to American arms and the explicit backing of the post-coup Ukrainian state.

To the extent that Russia's war in the Ukraine constitutes imperialism, it's almost entirely a reaction to the continued campaign of imperialist looting that NATO has waged since the collapse of the USSR.