SELECT 
  cscart_product_feature_variants.variant_id, 
  cscart_product_feature_variants.position, 
  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 = 'en' 
WHERE 
  cscart_product_feature_variants.variant_id IN (
    5773, 5870, 5936, 6063, 6065, 6066, 6067, 
    6069, 6070, 6071, 6072, 6073, 6074, 
    6075, 6076, 6077, 6078, 6080, 6294
  ) 
ORDER BY 
  cscart_product_feature_variants.position ASC, 
  cscart_product_feature_variant_descriptions.variant ASC

Query time 0.00051

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE cscart_product_feature_variants range PRIMARY PRIMARY 3 19 Using index condition; Using temporary; Using filesort
1 SIMPLE cscart_product_feature_variant_descriptions eq_ref PRIMARY PRIMARY 9 mahm3t_cs443.cscart_product_feature_variants.variant_id,const 1 Using where

Result

variant_id position variant
6063 30 300
6294 32 325 kg/m³
6065 40 400
5870 45 YTONG
6069 50 5
6066 50 500
6067 60 600
6070 75 7.5
5773 90 SOLBET
6071 100 10
6072 115 11.5
6073 150 15
5936 170 Traders
6074 175 17.5
6075 200 20
6076 240 24
6077 300 30
6078 365 36.5
6080 420 42