The One Switch site, dedicated to creating accessible games for switch users, has written an article about how to create a switch-accessible menu.
A particularly interesting tip is “start one-switch scanning, then switch to two-switch scanning if the user operates a second switch”. This makes your program one- or two-switch agnostic – you are handling both use cases with a simple detection of a feature, rather than requiring another setting screen.
Of course, some of the tips might be detrimental for screenreader users (such as the typical WebbIE users). For example, many switch users benefit from menus or lists that loop – when you go off the bottom of the list you start again at the top. But screenreader users generally like to know when they are at the end of a list (WebbIE programs tend to play a sound to help identify the beginning or end) because it provides orientation, since they can’t see the screen, and jumping up and down the list is easier for them (usually by pressing the initial key for a menu item – which is a reason to alphabetically-order your lists). The key thing is to identify your audience.