SELECT 
  cscart_product_feature_variants.variant_id, 
  cscart_product_feature_variants.position, 
  cscart_product_feature_variants.color, 
  cscart_product_feature_variant_descriptions.variant 
FROM 
  cscart_product_feature_variants 
  LEFT JOIN cscart_product_feature_variant_descriptions ON cscart_product_feature_variants.variant_id = cscart_product_feature_variant_descriptions.variant_id 
  AND cscart_product_feature_variant_descriptions.lang_code = 'ru' 
WHERE 
  cscart_product_feature_variants.variant_id IN (
    96, 90, 105, 116, 107, 113, 118, 119, 136, 
    120, 124, 122, 123, 191, 190
  ) 
ORDER BY 
  cscart_product_feature_variants.position ASC, 
  cscart_product_feature_variant_descriptions.variant ASC

Query time 0.00147

JSON explain

{
  "query_block": {
    "select_id": 1,
    "filesort": {
      "sort_key": "cscart_product_feature_variants.position, cscart_product_feature_variant_descriptions.variant",
      "temporary_table": {
        "nested_loop": [
          {
            "table": {
              "table_name": "cscart_product_feature_variants",
              "access_type": "range",
              "possible_keys": ["PRIMARY"],
              "key": "PRIMARY",
              "key_length": "3",
              "used_key_parts": ["variant_id"],
              "rows": 15,
              "filtered": 100,
              "index_condition": "cscart_product_feature_variants.variant_id in (96,90,105,116,107,113,118,119,136,120,124,122,123,191,190)"
            }
          },
          {
            "table": {
              "table_name": "cscart_product_feature_variant_descriptions",
              "access_type": "eq_ref",
              "possible_keys": ["PRIMARY"],
              "key": "PRIMARY",
              "key_length": "9",
              "used_key_parts": ["variant_id", "lang_code"],
              "ref": ["cscart.cscart_product_feature_variants.variant_id", "const"],
              "rows": 1,
              "filtered": 100,
              "attached_condition": "trigcond(cscart_product_feature_variant_descriptions.lang_code = 'ru')"
            }
          }
        ]
      }
    }
  }
}