SELECT 
  lang.name, 
  IF(
    cscart_ult_language_values.value IS NULL, 
    lang.value, cscart_ult_language_values.value
  ) as value 
FROM 
  cscart_language_values lang 
  LEFT JOIN cscart_ult_language_values ON cscart_ult_language_values.name = lang.name 
  AND company_id = 1 
  AND cscart_ult_language_values.lang_code = lang.lang_code 
WHERE 
  lang.lang_code = 'uk' 
  AND lang.name IN (
    'cart_info', 'information', 'catalog', 
    'cart_info', 'information', 'catalog'
  )

Query time 0.00040

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE cscart_ult_language_values system PRIMARY 0 const row not found
1 SIMPLE lang range PRIMARY PRIMARY 392 3 Using index condition

Result

name value
cart_info Інформація сайту
catalog Каталог
information Інформація