Hi,
There is no acruel key option in case of shipment pricing procedure. The GL account is determined based on shipment cost item categories and the valuation class assigned.
As of my knowledge, there is no option in standard to determine different GL based on shipment condition types. Instead, you may define different shipment cost item categories and assign different valuation class in T_56 transaction and define the different GL based on the valuation class in OBYC. You may even define a manual shipment cost item category in which user can add the shipment cost item category manually and add the extra charges.
Otherwise, you may check the feasibility of development.
Regards,
AKPT