It’s not uncommon for fascists to adopt socialist rhetoric to try and gain mass appeal. However that falls away under the lightest scrutiny of their actions and ideology. “National Socialism” is the most obvious example. I’d include Pol Pot in that bucket as well.

The USSR under Stalin and PRC under Mao are a bit different. The government in either case made decisions that led to unnecessary death, but there’s no evidence to suggest any of their missteps were motivated by racial animus.