[Clockworx]

I haven't watched any yet so if i'm wrong i'm wrong... But my understanding was in universe they just sorta exist. Theres a reason its "megalodon genome" and not "decade form" The fact that it looks like decade is a 'coincidence' and I'm sure when the inevitable cross over movie comes along and Revi meets whatever riders. with past riders there will no doubt be some "hey why do you look like me"

Naturally its the 50th annviersary of the franchise so theyare trying to cash in on that but since we just had the Heisei 20h a few years ago I don't feel like the past riders will show up and such and any in universe similarties are just a coincidence. but again i haven't watched any Revice yet so i could be totally wrong... and hell since its still early on for all we know in the last 10 episodes we find out theress some legit reason why his geneomes resemble past riders (other than o make Bandai more money)

As for the 'adaptation' well it depends... are your adapt ideas set in a shared universe? Do their powers have some connection to something LIKE he morphin grid? i mean maybe Revice adapt could be in a world where these forms of his are inspired by characters from some movie franchise or something?

Why does his Shark form look familiar? He based it on some character from a movie/book/show. Or even based it on some hero who the person who makes said gear saw when he was younger or something.