There’s guilds that have no problem with Forsaken or DKs. But they might not be loyalists or they may not be Forsaken/dead peoples focused. Some are cultists or dabblers in the Dark Arts and some are military units and everything in between. Depends really on what you have in mind for your character.
Couple of suggestions:
Alphabetical listing of guilds starts in the second post. Not sure when it was last updated as there’s at least one guild that has undergone a rebranding but the old name is still listed. Still a decent place to start.
The New to MG Horde discord:
https://discord.gg/SmRpCfS
Always recommend checking in here as there are helpful folk available that are more knowledgeable than I.
Finally, the Horde Guild Expo should be taking place next Friday June 19th at 9pm server time in the Valley of Honor. If you want to speak with/RP with a few organizations I’d definitely check it out.
Thanks for your patience. We aren’t as big as the Horde population you may be used to but there’s a whole lot of people working hard to help it grow and thrive.