You can exclude the stock movement posting as long as the stock is in the dock: for this you just need to set a formula on the auto journals. 
But once, you received the stock: the AVC is updated. Then, don't you want to pre-receive the order instead of doing a dock location receipt? In that case, the stock is not yet created.

You can use the AVC lot method instead. By simply, creating a new lot at each receipt, you won't have an impact on the existing stock value upon a dock receipt. If you don't manage lot currently, you may try the optional lot mgt and managed a receipt with a lot number defaulted from the receipt number for instance.

Last, would be to manage 2 sites: one for the dock and one for the rest of the stock. But this method is a huge change and increase the complexity of the managent of the solution: more product-site records, inter-site transfer transactions to do instead of a storage plan, MRP need to be set with inter-site supplier for the related products, you need to ensure the invoice adjustment are properly push to the 2nd site (using cost issue adjustement).

Hi Julian 

Thank you for helping me 

can you tell me more about (pre-receive) it seems like the optimal solution here ?/ 

Sure, this function is available since v11: Purchasing > Receipts > Order pre-receipt
Pre-receipts are meant to foresee the effective receipt of ordered goods based on information provided by the supplier. You can update the planned receipt date and enter the quantities that will effectively be received. Pre-entering this information will contribute to the optimization of the supply process, help avoid stock shortages and notify customers of late or incomplete deliveries.

The purpose of the pre-receipt function is to update the expected quantities and receipt date (this is taken into account in the MRP).

The stock is not created but you need to create the receipt by picking the pre-receipt instead of the order.

Thank you so much