нужно количество совпадений больше 3 not match_id:
SELECT Players.Nickname, Accounts.Email,
players.GlobalLevel,count(PlayHistory.MatchID) matchCount
FROM Players
INNER JOIN Accounts on Accounts.AccountID = Players.PlayerID
INNER JOIN PlayHistory on Players.PlayerID = PlayHistory.PlayerID
WHERE Players.GlobalLevel >5
GROUP BY Players.Nickname, Accounts.Email, players.GlobalLevel
HAVING count(PlayHistory.MatchID) >3
ORDER BY Players.Nickname ASC