What year is your bike?
Looks like there was an internal change between model years. For example:
2012: p/n 23P-8592A-00-00
2019: p/n 2BS-8592A-10-00
Typically, OEM sensors are just relabeled sensors from one of the major sensor manufacturers (Bosch, AC Delco, Denso, etc). Problem is, I don't know which brand Yamaha uses, or if they indeed make their own. I usually try to stay with the OEM brand on O2 sensors, as they are among the most important sensors on the engine, and some aftermarket sensors don't play well with stock ECUs. It looks to me like there are aftermarket brands available for the Tenere, but they're still nearly as expensive as OEM, and I've no idea if they might cause compatibility issues -- as such, I can't personally recommend them. If I were in your shoes, I'd stick with OEM to be certain, but we can try to hunt down the cheapest source.
The other problem I have is that I don't like replacing parts "willy-nilly" without good reason to believe that the old ones are faulty, especially when the parts are expensive (-the exception being if they're very old). Narrowband O2 sensors will rapidly oscillate between 100mV (lean) and 900mV (rich) when warmed up in closed loop. A bad sensor will usually stop oscillating and hover at one spot, which causes long term fuel trim to bottom out or max out. But you'd need diagnostic hardware/software (or oscilloscope) to verify. You might be able to bench-test it with a propane torch and voltmeter, but that's getting into areas that may be more trouble than they're worth.
Probably more information that you were looking for, but it's there if you want it. Others may have different opinions.