You can also assign commissions to POS orders. Unlike sales orders you cannot use the multi-commission function of TRX, but there are ways to create multi-commissions on an order. Aside from the multi-salesperson exclusion; commissions will work the same way in POS as they do in order entry. The commission will be based off of the salesperson that is placed on the order. You will not be able to view any commission information on a POS order as you can a sales order, but all POS transactions create sales orders that can be queried for viewing purposes. 
...
Depending on your TRX setup choices the Salesperson can be changed on a POS transaction.