How many sets are available just in Japanese and not in Magic: The Gathering Online?
Japanese refers to language = 'Japanese'; not in Magic: The Gathering Online refers to mtgoCode is null or mtgoCode = ''
SELECT COUNT(T1.id) FROM sets AS T1 INNER JOIN set_translations AS T2 ON T2.setCode = T1.code WHERE T2.language = 'Japanese'  AND (T1.mtgoCode IS NULL OR T1.mtgoCode = '')