With the In- Each Category based rule, you can provide discounts based on the quantities purchased in a combination of Categories.
For Example: Buy 1 product from Category A + 1 product from Category B + 1 product from Category C give a 10% discount in the cart.
This will allow us to get a discount of 10% only when the cart contains 1 product from each of the 3 categories A, B, and C.
These conditions will be in Rules(optional).
These conditions will be in Rules(optional).
Let's see with an example:
Go to WooCommerce -> Woo Discount Rules.
Click Add New Rule.

Scenario 1
10% when 1 product from each of the 3 categories A, B, and C are purchased.
Rule Setup:

Here is the cart page screenshot:

Scenario 2
Provide a fixed discount of 100 per set when 1 product from each of the categories A and B are purchased.

Cart Page Screenshot

Note :
Discount will be applied only when there is 1 product from each of the categories.
The discount will only be applied to the Categories you are selected in the dropdown.
Video:
Still unclear?
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