No, you cannot easily swap-out an OEM either-side muffler. The exhaust is 4 header pipes, and a combined, welded-together resonator box/twin megaphone system. See #43, below. Note the OEM system has
both a cross-over pipe for the front headers and the resonator box for the rear megaphones. There is an aftermarket twin megaphone, by Delkevic, which has a cross-over pipe instead of a resonator box, and two separate megaphones. Wait, I took a look, and that is no-longer available. Here are the current exhausts from Delkevic for a Generation 1:
https://delkevic.com/exhausts-filter/?exhausts=motorcycles_yamaha
This one may be the best of what they have, now, a slip-on for a quieter presence than the shorty exhausts they also have, and being chrome:
View attachment 94378
View attachment 94379
https://www.ronayers.com/oemparts/a/yam/500456a5f8700209bc79313b/exhaust