There is an Environment Overrides panel in the toolbar on top of Xcode's Debug Area. It allows you to select some of the most common accessibility options and Dynamic Type sizes, like in the Accessibility Inspector, plus select dark/light mode.
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The Accessibility Inspector lets you configure on or off some of the most common accessibility options so you can conveniently observe how your app adopts these options in the simulator or device. You can also quickly select different text sizes.
The fastest way for testing Dynamic Type while developing, and to quickly see how your app's UI flows, is by using the "option + cmd + plus/minus" to increase/decrease the text size in your simulator.
If you use Interface Builder to build your app’s layout, there are some basic accessibility attributes that can be configured from there. They can be found in the Identity Inspector in the right-side panel in Xcode.
