In previous versions of Odoo (13, 14, 15, 16), it was possible to add extra fees to online transactions. This feature seems to be missing in version 17. 

Does anyone know if this feature will return in v18, and if there is a current workaround for v17? 

From v16 documentation: (Extra Fees) To enable this feature, go to the Fees tab of the selected payment provider, enable Add Extra Fees, and configure the settings to your liking. 

I am very grateful to anyone that has a solution, or can even point in the right direction. 

Thank you.