Any "Customer Pricing", "Quantity Prices" or "Sell Price Tiers" set against products and customers in Unleashed will automatically sync to the B2B Store, and will apply to the appropriate customer's view of products of the B2B Store. 

Pricing for the B2B Store can only be set and managed from Unleashed, through the respective product or Customer records. Pricing and discounts cannot be applied or adjusted in the B2B Store directly.

For more details on how Unleashed and the B2B Store apply pricing, see What is the Customer Pricing Hierarchy?