Like Miss Change, Miss Granny or secret garden

Body swap:

  • Spring turns to spring - two women switch bodies 
  • Oh lala couple - couple switched bodies
  • Papa To Musume no Nanokakan /seven days of a daddy and daughter - father and daughter switched bodies
  • Switched - popular student switches body with unpopular classmate
  • Daddy you, daughter me - Korean movie version of seven days of a daddy and daughter
  • Big - student soul transfers into the FL's fiancee
  • Proud of love - leads switched bodies
  • The Miracle - fraternal twins switched bodies
  • Kimi no na wa -anime movie of leads switching bodies
  • Leh lub salub rarng - leads switch body
  • Please comeback Soon Ae - when the wife and mistress switched bodies
  • Yamada kun to 7 nin no Majo - switched  bodies of leads
  • The dude in me - Kmovie of a cop finds himself in a strange teenager body 

Boyd changing age (getting younger or older)

  • Radiance/the light in your eyes- FL becomes old
  • Sumire sumika- FL is an old lady and becomes young
  • I love lee taeri - ML becomes older
  • Mr.baek - ML is an oldman who becomes young again

Others:

  • Beauty Inside - movie  where ML changes body everytime he falls asleep or in the drama version FL changes appearwnce once every month  
  • The miracle that we met - ML dies and wakes up in a different body
  • please come back mister - leads dies due to some grim reaper mix up and they are brough back into other bodies
  • oh my ghostess - ghost possession
  • 49 days - ghost possession
  • Abyss - leads change their bodt after they die and get resurrected

Reon 

it was a funny movie (I watched it on the airplane) FL switches body with an older man

Omg there's a japanese drama in which an old lady becomes her younger self and falls in love with her school mate but I don't recall its title :|

boku wa mari no naka