Will GTA 6 have mod support?
The direct answer
Unconfirmed. Any modding would depend on a PC version, which Rockstar hasn’t announced. Consoles won’t be moddable, and online modding will be blocked.
Rockstar has historically tolerated single-player mods on PC while aggressively blocking anything that touches GTA Online. Since GTA 6’s PC version isn’t even confirmed yet, mod support is doubly uncertain.
If a PC version arrives later, expect an active single-player modding scene as with GTA 5 — but nothing about mods has been officially confirmed for GTA 6.