On the RMT specifically, Dempsey is proper fucking dodgy on this stuff and has been for years, see:
morningstaronline.co.uk
Profile of the Assassinated Rebel Militia Leader Mozgovoy
As has been documented on here in the past,
Dempsey along with Alex Gordon did security for a Vanessa Beeley meeting on Syria in London in 2017, the two of them are now RMT AGS and President respectively.
More generally, I suppose you can distinguish between "hard" and "soft" pro-Putin positions - being explicitly pro-Putin is pretty rare, although it does happen, but I think that... the vast majority of the left can probably all basically agree that "Russia invading Ukraine is bad, NATO does bad things as well, there are some nazis in Ukraine", and indeed also "to the extent that we can affect anything we're more able to influence Johnson than we are Putin", but then that leaves a lot of room for difference in emphasis, from people who think it's currently more important to stress "Russia invading Ukraine is bad" more than anything else, to people who want to emphasise "Russia and NATO both do bad things" an equal amount, to people who will go through the motions of condemning the invasion but get it out of the way as quickly as possible before concentrating on their main points about NATO being bad and how there are nazis in Ukraine.