The values that used to be available on the "Variation" tab are now directly available in the "rules" via "Attributes Matching".
For these fields, match values from your catalogue with expected values from the channel using conversion lists.
- Most common variations (size and color) are gathered at the categories attributes levels.
- The conversion lists allows you to match data from one of your field to valid values from the channels, using only one rule.
When you add new variation values, you just have to fill in the list.
Read another article specifically: