If you wish to switch Factions, you will need to remove all Faction-tagged items first and you will lose all Favor, however your Reputation and Rank do not reset. In the case of Circle of Fortune (CoF), you will also lose any active Prophecies. As 'Switching Faction' data is connected to the player's stash, this will also affect all characters that share the same stash.
Items found as a result of your CoF bonus are tagged with a CoF Rank requirement. There is no way to remove this requirement. In order for anyone to use a CoF Rank required item, they must currently be representing that Faction at at least that Rank.
If you have several CoF Rank required items and you switch to Merchant's Guild (MG), you will not be able to use those items while you are MG. If you switch back to CoF you will be able to use those items again.
Circle of Fortune is the non-trade Faction but in no way restricts you to playing solo.
There is no "account bound" for items. However, items with either Faction Rank requirement cannot be sold at the Bazaar.
None of this affects the Party Gifting or Resonance systems.
How to change Factions:
- Once in game, open your Factions window (defaulted to "Y" keybind).
- Click on "Rank and Reputation" of your current Faction.
- Click on "Leave Faction" on the upper right of the window.
- You will get a prompt to confirm leaving the Faction, click "Yes".
- You will now be able to travel to the other Faction's NPC (by clicking on "Visit Observatory" (for CoF) or "Visit Bazaar" (for MG) and join.