I'm looking to convert an ed25519 private key to an rsa private key using `ssh-keygen`.

I found [this helpful guide](https://man.openbsd.org/ssh-keygen) but I am having trouble figuring out how to specify that the input format is ed25519 and the export format should be rsa.

I've tried a bunch of different ways trying to match the synopsis and the description of flags, but every time I try, I get "`Too many arguments`" error from `ssh-keygen`.

I'd also like to find the command to generate a public key from a ed25519 private key to verify that it works.