10 Popular Chinese Mid-Autumn Festival Greetings/Sayings

• Happy Mid-Autumn Festival!
  中秋快乐!
  Zhōngqiū kuàilè!
• Wish you and your family a happy Mid-Autumn Festival
  祝你和你的家人中秋快乐
  Zhù nǐ hé nǐ de jiārén zhōngqiū kuàilè
• Wishing us a long life to share the graceful moonlight, though thousands of miles apart.
  但愿人长久，千里共婵娟
  Dàn yuàn rén chángjiǔ, qiānlǐ gòng chánjuān
• A bright moon and stars twinkle and shine. Wishing you a merry Mid-Autumn Festival, bliss, and happiness.
  皓月闪烁，星光闪耀，中秋佳节，美满快乐！
  Hàoyuè shǎnshuò, xīngguāng shǎnyào, zhōngqiū jiājié, měimǎn kuàilè!
• Happy Mid-Autumn Festival! May the round moon bring you a happy family and a successful future.
  祝福中秋佳节快乐，月圆人圆事事圆满.
• The roundest moon can be seen in the autumn. It is time for reunions. I wish you a happy Mid-Autumn Day and a wonderful life.
  月到是秋分外明，又是一年团圆日，祝你节日愉快，身体安康
• Wish you a perfect life just like the roundest moon in Mid-Autumn Day.
  愿你的生活就象这十五的月亮一样，圆圆满满
• Happy Mid-Autumn Day! Wish that you go well and have a successful and bright future.
  中秋节快乐，万事如意，心想事成!
• I want to make a toast. I Wish that the round moon take my best blessing to you. May you have a happy family and a bright future.
  举杯仰天遥祝：月圆人圆花好，事顺业顺家兴。
• I wish that your career and life, just like the round moon on Did-Autumn Day, be bright and perfect.
  祝你的事业和生活像那中秋的圆月一样，亮亮堂堂，圆圆满满

Source: https://www.chinahighlights.com/festivals/mid-autumn-festival-greeting.htm