Apply a discount to the purchase when choosing a shipping method that has cost 0

Good Morning,
I want to make a discount of 5% to select the shipping method " Store Pickup " which is a method of free shipping, because the client would come to the store to pick up the order and not have to send the package. Is there any way to make this discount?

Thank you very much

Hello,

You could use a parent coupon:

Coupon A: shipping coupon where you select store pickup with 0 discount
Coupon B: the 5% discount coupon
Coupon C: parent coupon where you add coupons A and B and set function type to Only if all apply

Then give out coupon c.

Thank you very much , and I've got to do with your instructions .

Greetings,

Manuel