As far as I know you can specify a pricelist for a client. When the client is doing his order, that pricelist is used instead of the default pricelist.

I am in the process of setting up the following structure:

1. General sales list
2. Country list (for every contry the company is having customers)
3. Discount per country list

List 3 is pointing to the relevant country list2, which in its turn is pointing to the general sales list.

Example: I have a country sales list (level 2) 'Netherlands', which is pointing to general sales list. I hva a list (level 3) '5% discount Netherlands', which point to the country sales list 'Netherlands' I also have a list (level 3) '10% discount Netherlands', which also point to the country sales list 'Netherlands)'.

On the customer from The Netherlands with 5 % discount, I add the list '5% discount Netherlands', when the customer is having no discount, I add 'Netherlands' as default list.

In this way you can create multiple 5% discounts, one for each country you are having customers.

I hope you get my structure.

Setting up the structure might take some time, but once setup, there is not much to do. I have a script to setup a whole set of these things, which reads a csv-file to create everything. Feel free to contact me if you are interested.

Take a look at this - https://www.odoo.com/documentation/user/9.0/point_of_sale/advanced/manual_discount.html

KM