different keys on a Maestro

Short A: no

Longer A: The Maestro has a single Key-In jack, and it must be configured for either a straight-key (single-contact closure) or a paddle (double-contact with individual dot and dash closures).

One scenario: you swap your keys and paddle, then re-configure the Maestro. Personally, I'm too lazy to enjoy doing this ☹️

Second scenario: add an external keyer of some sort, then parallel this keyer output with your single-contact key(s). I do this, with a WinKeyer and my bugs / straight-keys. Now, you can shift between keyer / key in mid-conversation - I tend to do this quite a lot.

To help with my desire for flexibility, I built a small project-box with about 6 1/4" jacks and a couple of 1/8" jacks, all wired in-parallel. One serves as the output to go to the Maestro (or Flex key-in, or Kenwood key-in, or Heathkit key-in). The others can accommodate a variety of other keys, to suit my mood. My VibroKeyer with WinKeyer is one of the inputs to this junction-box, appearing as a single-contact-closure in parallel with bugs and keys.

You could take a board, drive a couple of nails, connect those to your Maestro / Flex, then clip on keys / keyer as you see fit 😂 Some might say "nostalgic" while others might say "janky" 🤣

But then wading through menus, to turn Iambic off / on…you lose that magical moment 😯