You can post AI music straight to SoundCloud from ElevenLabs

SoundCloud has added an integration with ElevenLabs that lets users publish their AI-generated tracks directly to SoundCloud instead of exporting and re-uploading them, and songs published this way will be labeled as AI-originated. SoundCloud Artist Pro subscribers also get three months of ElevenMusic Pro free as part of the partnership, which is less deep than SoundCloud's earlier Moises integration.