For ∞Grpd the (∞,1)-category of ∞-groupoids, and for a (∞,1)-category (or in fact any simplicial set), an -presheaf on is an -functor
The -category of -presheaves is the (∞,1)-category of (∞,1)-functors
A model for such -presheaf categories is the model structure on simplicial presheaves. See also the discussion at models for ∞-stack (∞,1)-toposes.
see also
section 5.1 of