Can I edit the A+ wording after export?

Text that's part of the image is set in the A+ Creative tool — change it there and re-export the image (re-exports are free once the book is unlocked).

Separately, Amazon's A+ modules often have their own text fields (headings and body text that sit beside or below the image); you edit those directly in Amazon's A+ Content Manager when you build the project. So between the two, you have full control over the wording — just keep it within Amazon's content rules.