SELECT 
  variant 
FROM 
  cscart_product_feature_variant_descriptions 
WHERE 
  variant_id = 123 
  AND lang_code = 'en'

Query time 0.00020

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE cscart_product_feature_variant_descriptions const PRIMARY PRIMARY 9 const,const 1

Result

variant
Atlas