XEdit

More detailed info here

Accepts the following command line arguments in order to set the game mode:

• -Enderal
• -Enderal SE
• -FO3
• -FNV
• -FO4
• -FO4VR
• -FO76
• -SSE
• -TES4
• -TES5
• -TES5VR

Final releases are available on the Nexus page of any supported game.

Latest non final releases are available on the xEdit Discord

For Fallout 3 and Fallout: New Vegas, the latest known version of xEdit without issues is 4.0.3, so if you encounter issues after saving with more recent versions, try editing with that version instead.