Hilchos Shemittah v’Yoveil 6:4

Things that are normally bound to bring home may be bound the same way to sell in the market by approximation; one may not bind such things in the way they are normally bound for sale. If something is only bound for sale in the market, it must be sold unbound.

Hilchos Shemittah v’Yoveil 6:5

If produce from outside of Israel was brought into Israel during shemittah, it may not be sold by volume, weight or count. Rather, it must be sold by approximation the same as the produce of Israel. If it’s obvious that the produce came from outside of Israel, then it may be sold in the usual way.