Commerce 2.x attribute translations cause product duplicates in views
I found a way to solve this. You must:

1) ensure you have a variations delta filter set.

2) add the field variations and ensure that the Display all values in the same row is NOT CHECKED under Multiple Field Settings. you can then hide this field if you do not want to display the output.

3) in the view display's Query settings tick the check box Distinct.

This configuration will remove product duplicates when the Product Variation relationship is used. This is the resulting query, i am not sure how efficient this configuration is but at least it works.

SELECT DISTINCT commerce_product__variations.delta AS commerce_product__variations_delta, commerce_product__variations.langcode AS commerce_product__variations_langcode, commerce_product__variations.bundle AS commerce_product__variations_bundle, commerce_product__variations.variations_target_id AS commerce_product__variations_variations_target_id, commerce_product_field_data.product_id AS product_id, commerce_product_variation_field_data_commerce_product__variations.variation_id AS commerce_product_variation_field_data_commerce_product__vari
FROM 
{commerce_product_field_data} commerce_product_field_data
LEFT JOIN {commerce_product__variations} commerce_product__variations ON commerce_product_field_data.product_id = commerce_product__variations.entity_id AND (commerce_product__variations.deleted = '0' AND commerce_product__variations.langcode = commerce_product_field_data.langcode)
LEFT JOIN {commerce_product_variation_field_data} commerce_product_variation_field_data_commerce_product__variations ON commerce_product__variations.variations_target_id = commerce_product_variation_field_data_commerce_product__variations.variation_id
WHERE commerce_product__variations.delta = '0'