The plushie is the best I've seen.

Bitcoin Magazine

Merchants Don’t Read White Papers, They Read Cash Flow Statements

Why the argument for bitcoin to merchants is profit, not theory, and how we can make that case at their registers.

Bitcoin Merchant Community

Bitcoin Merchant Community

The Bitcoin Merchant Community is a growing global community of small businesses helping one another defeat 3% credit card fees by accepting bitcoin

I had built a PoS system for a coffee shop in 2020, that accepted Bitcoin for payment; using a proprietary payment system. Also made these 2x2 stickers the owner put on the coffee cups. I would hope Square had something like it!