the Great Powers for Battle Fever, Denjiman and Gavan seem to show up in the movie:
Battle Fever J- Battle Fever Robo
-Vamcuria, Yatsudewani, Bae are rumored to appear in Gokaiger VS Gavan
-The main antagonist of the film seems to be a son of Don Horor, Ashuraada. He copies Gavan's abilities and becomes a Gavan Bootleg.
-Weevil (played by Sano Shirou) appears as Gavan's boss. However, he is really a wirepuller who is working with Zangyack
-Akudos Gil, Dairandor (one of the bodyguards) and Insarn will appear in the movie representing Zangyack. Akudos will be voiced by Ogawa Shinji, Dairandor will be voiced by Ebara Masashi
About the plot:
"Uchuu Keiji Gavan,” who is celebrating its 30th anniversary, the character was chosen to team up with “Kaizoku Sentai Gokaiger” for the new movie. Gavan aired in 1982-1983 as the first show in the Metal Hero Series, which lasted until 1999. The show averaged 14.9% ratings, with a peak of 18.6%.
In “Kaizoku Sentai Gokaiger vs Uchhu Keiji Gavan,” the Gokaigers will rescue Gavan from the worst prison in space, and then teaming up to fight against the one of their strongest enemies ever. Probably Basco as he tries to steal his Great Power.
Kenji Ohba will guest star is the movie as Retsu Ichijouj, a.k.a. Gavan. Not only that, he will also transform to his other characters, namely Battle Kenya (Battle Fever J) and Denji Blue (Denji Sentai Denziman).
“Kaizoku Sentai Gokaiger vs Uchhu Keiji Gavan” will premier on January 21st.