The protagonist here is a girl from beginning to end, so please keep that in mind. Also, this protagonist is another incarnation of the protagonist from one of my other books.
A fragment of a girl's soul transmigrates and becomes a World Tree. Another girl discovers her, then has her friends keep her company and sends her to other worlds to get familiar with energy. Along the way, she occasionally chats and trades snarky remarks with original Kamen Rider belts that have consciousness of their own. This is a multi-world transmigration story.
The belt, however, finds it a headache that this girl is hardly a nerd at all, so it has to explain the characters they encounter to her.
Worlds visited: Touhou Project (The Tale of the Bamboo Cutter) → chaotic American comics (Marvel side story: starting a business making belt accessories) → [this volume is being revised] → Gonna Be the Twin-Tail!! (complete chaos) → Gate: Thus the JSDF Fought There (a girl's journey as a charlatan) → Kamen Rider Drive (fighting alongside a veteran rider) → Touhou Project (the origins of Gensokyo) → chaotic American comics (mainly Marvel, with occasional plots from other comics or movies mixed in) → A Certain Magical Index series (flirting with a few girls) → Re:CREATORS (main story complete)
P.S. Some characters may be out of character. Please think of all the worlds as parallel worlds where the characters are similar.