We have a company that have two main warehouses, they purchase their goods and receive it in wh1, then they do landed cost 1. Once they sell a product, they ship it to the wh2, then they add landed cost2 specifically to one peace. 

The difference is that they add total landed cost to the total receipt in the wh1, but in the second transfer they add landed cost only for specific products, and as you know we can't add landed cost for internal transfer it is a bit of challnge.

We tried using routes to do internal transfer to a receipt location but it made some problems in the stock valuation.

I also had a look on this question:

https://www.odoo.com/forum/help-1/adding-landed-cost-for-internal-transfers-177878

Not sure if it will work in our case, since we can't create receipt from wh1 as a source(vendor)

Also we need to generate a report to check the cost at two different warehouses