Inovelli may have one soon — this project has been announced: Z-Wave 5-Button Scene Controller + Dimmer Switch | Project Limitless. However, there haven’t been any updates in a while, and the originally-stated target completion date is soon approaching, so I’m guessing it’s delayed. There’s also this: Paddle Remote | Project BFF, but we already know that project is currently on hold.
Otherwise, what hub do you have? My favorite one-button buttons are the SmartThings Buttons, but those are getting harder to find as ST’s hardware business is in flux. Lutron Picos are my favorite all-around button device, but they only work with a Caseta or RA2 system or hubs that integrate with those (e.g., Hubitat, Home Assistant, etc.). A certain other Z-Wave manufacturer just came out with a paddle button that looks a lot like a “regular” switch, and as above, Inovelli will likely have one at some point, too. Beyond that, there are lots of things I’m not a fan of for gaudy looks or high prices like the Fiabro button and lots of remote-type devices. 