So here is the challenge find some way to get the Golden horde to convert to Orthodoxy instead of Islam like our timeline. So if the Golden horde does become Orthodox how would this affect Russian history and what would happen
A Christianity with a better bureaucracy would have been more valuable to the Mongols. That's one reason Christianity declined relative to Islam in the west and Buddhism in the east. You have to come up with a way to make eastern Christianity in the region more robust. In RoS the Jurchen-Koreans use the Christian tribes as a buffer to eastern militant Buddhist rivals so they're getting state support (and thanks to alt-Spain they were a little stronger in the first place). It's going to end up being a weird version of course, but that's just how it goes.That might be difficult. The only Christianity the Mongols seem to have seriously toyed with was Nestorian.