Resources to dispel Russia and China imperialism myths?

cross-posted from: https://hexbear.net/post/6792069

I've been running into this conversation quite a few times recently with fellow organizers: that China and Russia are imperialist powers because they are expansionist. While I understand in my brain why this is not the case, it is difficult for me to argue the case. I wonder if there are any useful (and short) analyses / frameworks I can use in a conversation, because I start losing people when I get too into depth in theory.