Question on transferring from one account to another

Apologies if this is posted elsewhere, but I'm curious -

I have two accounts, one that had primarily high levels on live servers, and one that was a much older account (originally my EQ1 account) that ended up having some TLE characters on it. My TLE account I actually ended up really enjoying a mule character and levelled her up, and preordered the expansion. I'm looking at how dead the server is, and not looking forward to trying to do all the RoS achievements without help, and am debating going to my other account that has all those things unlocked.

If I preordered on one account, and then wanted to transfer to another account that I did not preorder RoR on, do I keep the preorder pet if I've already claimed it/scribed it?

no. the pre-order is attached to the account, not the character.

This is Masynrae, successfully moved to my other account

I did retain my pre-order pet (already scribed) when I transferred accounts. I suppose if I had more money than sense and wanted to dust off last expac's top characters on my account I could pay to transfer back and forth to get the potency boost. I kind of like this though, forces me to focus on one character.