Based on your description, you’re creating something that simulates a bank statement, but not trying to replicate any real-world document for deception. As long as your templates are original in design, and you include disclaimers that they're fictional and for educational purposes, you should be in the clear. Many educators and trainers use similar documents in workshops or training sessions to help people understand how finances and statements work. Just be mindful not to copy any logos, brand colors, or specific layouts used by real banks. For these purposes there are templates https://bankstatementgenerator.org/product-category/usa-banks/ that can give you some hints about how everything work in this area, so feel free to use them