Bluetooth transmitter for connecting gaming controllers

Hi! I don't know if I'm posting in the right forum here - if I'm not, please feel free to move the post - but I'm hoping that someone here can help me out.  I'm usually pretty good with tech stuff, but this isn't something I've come across before.

I want to set up a NES emulator to run off my Amazon Firestick.  I have NES controllers that need to be connected via Bluetooth, but the issue is that my TV is not a smart TV and therefore doesn't have Bluetooth capabilities (it's a few years old and at the time I bought it, I wasn't thinking about that issue).  

So I've been looking online for a Bluetooth transmitter to buy, but - and this is where my question comes in and why I'm feeling a bit dumb, haha - they all make mention of connecting Bluetooth headphones and speakers.  None of them mention connecting gaming controllers.  So I'm wondering if I need a specific transmitter, or if any Bluetooth transmitter would work. 

If anyone can shed some light on this for me - whether I can buy any Bluetooth transmitter or whether I need to buy a certain one for gaming controllers - I would really appreciate it. Thanks in advance!

This is an interesting one!

Theoretically, as long as the bluetooth adapter you're purchasing supports the version that the controller uses, then it should work no problem. But televisions are a tad tricky, and in my experience, they tend to treat wireless/bluetooth devices differently then say; a computer.

Is the controller straight bluetooth - as in, there is no dongle at all? I did a quick search for controllers (mostly of out my own curiosity) and most of them seem to come with their own USB dongle for connection. Do you think you could link the exact controller you're using? I would love to see the spec sheet on it - it could help narrow down some options.

However, at the end of the day, this may be one of those "gotta try it and see" type of scenarios.