Recommendations

It's set in the world of Gods and Goddesses. The leads also go thru different trials. The best, is that both stories are happy ending despite all the tribulation and angst.

Both male leads are living in a parallel reality, both dramas have violent crimes in common and police investigations.

Both movies are way out there and extremely fun to watch, they were both so random that it was hilariously scary.

They're stories of first love that are both simple and beautiful. They're short, sweet, and reflects the bitter-sweetness of a first love.

both are abnormal doctors , both are itself a patient of incurable disease and great doctor as a same time, both FL try to help in their way to comfort ML

Both have darker, more mature themes and romances involving temptation and irresistible attraction with intense chemistry.

Very similar themes of anxiety about marriage and getting older, and both feature a surly ML who loves to lecture women on how to live their dating lives.

Similar themes of older woman/younger man, and in both the FL is struggling to get over a past/prior love.

Both of these have similar themes of a woman in her 30s presented with three men, struggles involving dating a younger man, and anxiety over marriage and getting older.

Very similar stories, both feature smart plots to enact revenge. Greed, corruption, powerful family, manipulation, hidden identity.

Although the stories are completely unrelated both dramas star Lee Seung Gi and Suzy as leads, if you like the pairing you will want to watch both dramas.

Mystic Nine isn't set in a military academy and has some fantasy elements but appearance wise the male leads give off the same vibe except Fo Ye in the Mystic Nine is super smart

- The main couples has a similar dynamic (funny and cute) when they are on screen together
- they are both set in the same time period with the Japanese taking over China
- there are a lot of good looking actors in both shows

Similarities:
Action, friendship, romance and military based training (takes place in a military academy) where the only female in the base is the female protagonist

-Both can have a light rom-com vibe but has those intense serious action moments too
Destined to love you isn't a crossdressing drama but the female lead also takes on a fake identity to become a military school instructor

-just like Arsenal Military Academy it take 2-3 eps to really start liking the cast and getting to know the military crew
-Destined to Love You has a high budget for costume designs so if you love military outfits this drama is for you!

I love both dramas and recommend them both

The Ghosts from both dramas cannot remember their pasts and why they died. They get to know later on in the story and why they could not go to heaven, reincarnate, etc.

Both are rather standard Chinese romantic costume dramas with beautiful costumes, fighting kingdomes, mad love, Mary Sue female lead and male lead called 'great warlord' (though it is not clear why he is great). If you are a shipper you'd like both