Do you have stock or custom firmware? Stock: pairing is NOT posible. Custom: i do not know.

You might want to look in to these or this (both have the ability to use a wide aray of modern bluetooth controllers

I own both products and I can confirm that the one in the box of this photo does not have Bluetooth support. It says it on their site and on the Amazon listing.

“2.4g Wireless Technology for original SNES/SFC *Bluetooth connection is not applicable”

This product is Bluetooth only. https://www.amazon.com/dp/B01K1T9CZS/ref=cm_sw_r_cp_api_glt_fabc_1T2R539AK88WJS43M84E

Bluetooth controllers will not work on the receiver packed in with this controller and the packed in controller will not work with any Bluetooth receiver.

I don't think they ever actually sold the SNES 2.4g receiver by itself, because those controllers only work with the type of receiver they came with. They do still sell the bluetooth SNES dongle though.