There isn't a lot of Christmas in tokusatsu but there is some. Two episodes I know of are:
Kamen Rider 12-25-1971 episode 39 Demon Wolf-Man's Huge Murderous Party
Wolf-Man (Okami-Otoko) threatens a Christmas party (Colonel Zol's last episode)
Kamen Rider V3 12/22/1973 episode 45 Destron's Xmas Present
Rhino Tank impersonates Santa Claus to abduct children, this makes V3 very angry
Kamen Rider Christmas
Vocals: Mizuki, Ichiro & Columbia Cradle Club
Music: Kikuchi, Shunsuke
English translation: Steve Okubo
Kamen Rider has arrived
Christmas has arrived
Rider Rider Christmas
Everybody, everybody transform!
You are a Rider, I am a Rider
Do not fear the Shocker Army
Jump Go! Kick Go!
Those on the side of good will always win
Rider Rider Christmas
Your red muffler is cool
Coming to Christmas town
Rider Rider Christmas
Everybody, everybody transform!
Do not fear the evil army
Hook Go! Cut Go!
Those who do there best will always win
Rider Rider Christmas
On your lightning machine you have arrived
Christmas has rapidly arrived
Rider Rider Christmas
Everybody, everybody transform!
You are a Rider, I am a Rider
Soon a bright Spring will come
Jet Go! Chop Go!
Whistle! Clap your hands!
Rider Rider Christmas
Gojira (Godzilla) and Barom-1 also have Christmas songs but I don't have translations of those. I don't know if Chôjin Baromu-1 had a Christmas episode to go with the song.
If any one would care to translate Christmas of Super Human Barom 1 I have the Japanese lyrics at
incolor.inetnebr.com/stuart/collect/coshb1.htmShinnen omedeto