Especially slow query is the lower five.
SELECT title FROM `qa_posts` WHERE title = 'tryrtyrtyrtyrtyry؟ss؟' AND type = "Q" LIMIT 1
3361.35 ms - 0 rows - 1 column
INSERT INTO qa_options (title, content) SELECT 'cache_qcount', COUNT(*) FROM qa_posts WHERE type = 'Q' ON DUPLICATE KEY UPDATE content = VALUES(content)
383.21 ms
INSERT INTO qa_options (title, content) SELECT 'cache_unaqcount', COUNT(*) FROM qa_posts WHERE type = 'Q' AND acount = 0 AND closedbyid IS NULL ON DUPLICATE KEY UPDATE content = VALUES(content)
2347.10 ms
INSERT INTO qa_options (title, content) SELECT 'cache_unselqcount', COUNT(*) FROM qa_posts WHERE type = 'Q' AND selchildid IS NULL AND closedbyid IS NULL ON DUPLICATE KEY UPDATE content = VALUES(content)
2699.90 ms
INSERT INTO qa_options (title, content) SELECT 'cache_unupaqcount', COUNT(*) FROM qa_posts WHERE type = 'Q' AND amaxvote = 0 AND closedbyid IS NULL ON DUPLICATE KEY UPDATE content = VALUES(content)
2103.15 ms
In summary, it appears that SELECT of qa_posts and INSERT of qa_options table are slow. It seems that specific (ONE) query is not slow.
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Q1) How many records are in the qa_options table?
Q2) Are there many wasted records in the qa_options table? <= Even if you delete Q2A plugin, option data will survive. It is known that some plugins create large amounts of data in option tables.
Q3) Can you update my.cnf? (Your server is VPS / Dedicated server?)