No, we do not support MongoDB. If the MongoDB decide to build a connector (which is looking highly unlikely at this point) it would be up to them to write that type of guide.
Strapi (the company) will no longer support (meaning we will not focus any effort) on NoSQL or MongoDB for the foreseeable future unless it’s to lend help to a team to integrate their own custom connector into our ecosystem (that doesn’t mean we will help them build it).