The workshop content is located here: C:\Program Files (x86)\Steam\steamapps\workshop\content\255710 right click on DOTA2 and go to 'Properties'. But it is still possible to use workshop content by copying the files from the workshop folder to the local mods and assets folders. Local Mods & Assets In no workshop mode, only local mods and assets are loaded.
Many games support mods through the Steam Workshop, where you can easily browse for new content and have it automatically appear in your game.
Locate the SteamApps folder on the c: drive, it is located in Steam > Steamapps, usually in Program Files or Program Files (x86).