This takes place at Alien Force.
This is a Ben x Female Tsukasa Kadoya or Female Sougo Tokiwa.
But if you want it the other direction Tsukasa Kadoya and Sougo Tokiwa x Female Ben or more Appropriately Jen/Jennifer.
The over all plot of the Kamen Rider sides of things can be the same the writer is free to change what they see fit.
Decade & Zi-O have modern Rider power.