Hello! I wanted to ask if I can make and publish a Russian translation of this edition on itch.io? 

You can, follow the guide here: https://cairnrpg.com/localization/localization-guide/

However there is already a Russian translation for 2e that is nearly complete, you should reach out to the team doing that.

https://ru.cairnrpg.com/

Hi, I’m a publisher of Cairn 2e in Russian Language. Cairn 2e: BE is currently in a queue of Cairn projects we are working on. If you want to help us translate & publish this project. Write me at Telegram (@thevarik) or on my email (varik@hexcat.run).

I’m extremely open on working with people to make more good games hit the shelf.