Creation of purchase shipment cost invoice lines

I see that the purchase_shipment_cost module allows to set the shipment cost of the supplier shipment. This cost is added to the unit price of the moves but is never invoiced.

As the purchase module creates the invoice (or the invoice lines) for the supplier and we know that the supplier will invoice the cost of the shipment (otherwise we should not put any cost on it) I’m wondering we should not create an invoice line for it like we do on the sale module.

Does it make sense or am I missing something?

Indeed I’m wondering if the module should not be deprecated completely in favor of account_stock_landed_cost since we have automatic recomputation of the product cost.
The only advantage I see for purchase_shipment_cost is that it give an early estimation of the stock move cost that may be used by account_stock_anglo_saxon to set a better COGS in case the product is sold before the landed cost is applied.
If we keep both we need to make them compatible together, this means that the unit_shipment_cost should be removed if a unit_landed_cost is filled.

I agree that both modules have the same functionalities while the landed cost allows allocation of non shimpent costs. So for me it makes sense to unify both modules into a single one.

I think it is better to keep both but account_stock_landed_cost should be more an extension of the purchase_shipment_cost and correct the estimated shipment cost.