I don't see a public documentation for their API or payment interface so it is unknown at this moment if this Zelle system could work with WooCommerce or any other eCommerce platform. Try contacting their support.

I would buy a plug-in all day long. I am a big believer in buy vs. build. Buy buying you receive a proven product and usually you also get a product with a roadmap and future releases.

I have a lot of ecommerce and web experience please let me know if you would like to chat further about this.

Best to first contact Zelle + ask for their advice.

Likely they already have many answers/approaches.

Or try searching for something like - "zelle" wordpress plugin - or something similar.

Be aware Zelle has some serious flaws, that can cause your company to go broke instantly.

Best also search for something like - "zelle" fraud - which will likely cause you to instantly abandon Zelle.