I think Russia has mostly lost the perks of its USSR legacy in space to time, and I would argue has even less current experience than China on making new systems. Most of the USSR stuff would've been like NASA's stuff from that period, extremely reliant on the experience and intuitions built up by the engineers of the time such that reusing the designs from that time now is almost as much work as just designing a new thing from scratch. Russia hasn't invested in propagating that knowledge to younger generations, and the people from that time are quickly aging out of the workforce. So the only institutional knowledge they really have left at this point would be Soyuz, which, while a workhorse, is certainly not enough on its own to cover the systems needed on a space station/base of any sort.

JAXA, ESA are considered partners on the Artemis program (at least based on Wikipedia, there does not seem to be an explicit list of partners on NASA's site), they're training astronauts to eventually be sent to the Moon in a similar arrangement as with the ISS. JAXA and ESA (along with the Canadian Space Agency) are also contributing various key components for the Gateway space station. Plus, the ESA is an important player with the Orion capsule which Congress-critters seem committed to forcing to be the center of the program regardless of technical and financial sense.

As for ISRO, I think I mixed things up a little. I think I had heard talk about the potential for an arrangement to fly a vyomanaut to the ISS on Dragon, assumed that it was about the agreement having been made and then mixed it up with Artemis. Turns out none of that was real, there does not appear to be any talk of sending an vyomanaut to the ISS.