RM's Webhints for FamilySearch Family Tree also do not result in any exchange of data. RM does support data exchange with FSFT, but the mechanism for exchanging data with FSFT is totally different and separate from the mechanism for hints from FSFT. I don't think MyHeritage has an API that RM could use for exchanging data. RM can't exchange data with MyHeritage until and unless MyHeritage supports an API.
Absolutely nothing about Webhints is stored in your RM database, neither the Webhints for Myheritage nor the Webhint for FSFT. You can't search for WebHints in your RM database nor can you run reports against them. The only thing you can do is to go to somebody in RM's Family View, Pedigree View, or Descendant View and wait a few seconds to see if a light bulb is displayed. The light bulb is yellow if it is not confirmed and it is clear white if it is confirmed.
Whether the light bulb is yellow or white is not stored in your RM database. The confirmation of the hints is stored on the FSFT server for their Web hints and on the MyHeritage server for their WebHints. You can logon to the FSFT Web site and see the hints there as Record Hints. The hints are communal to the whole world, and the whole world can see them. Indeed, if another FSFT user has already confirmed a hint, it will show up in your RM as confirmed even though you didn't confirm it yourself. You can't logon to the MyHeritage Web site and see the hints. The only way to see the hints is through RM screens. And the MyHeritage hints are specific to you. They can't be seen by anybody else, even if they are running RM.