By erasing all content and settings is it all set for trade in

here is the support article for what to do before selling/trading in your device

What to do before you sell, give away, or trade in your iPhone, iPad, or iPod touch - Apple Support

I'd assume that you made a backup or whatever you needed prior to erasing the device.

If you have an Apple Watch and you didn't unpair it, that can be resolved later

One thing you might be missing is the part about signing out of iCloud. I think that Erasing all Content and Settings actually does this. But if you're concerned, you could check to see if it's still linked to your account. In the link I posted above, review #2 in the section called If you no longer have your iPhone, iPad, or iPod touch

There’s more to do!

What to do before you sell, give away, or trade in your iPhone, iPad, or iPod touch - Apple Support