I recommend running your app with Double-length Pseudolanguage. It is a great way to stress-testing your app and see how adaptive it is and if your UI will hold to other languages that might be a bit more verbose or even with larger text sizes.
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Sometimes, with large font sizes, there's no other way around it but to offer an alternative layout. Small tweaks are often enough. Otherwise, the text will be barely readable. Larger text shouldn't mean less content or a worse experience. One thing you can do is to check if the preferred content size category of a view is an accessibility category. And, in that case, move things around to make room for the text, offer more lines of text, etc. https://developer.apple.com/documentation/uikit/uicontentsizecategory/isaccessibilitycategory
If you want to keep yourself up to date with what’s going on, or what has been published lately, on how to develop more accessible mobile apps, make sure you subscribe to Accessible Mobile Apps Weekly by @RobinKanatzar from @accessible_apps.
Guidelines from Apple: Begin with a verb that explains the results of the action. Avoid using the imperative form of a verb because that can make it sound like a command. Don’t include the action type. Don’t include the control. https://developer.apple.com/documentation/objectivec/nsobject-swift.class/accessibilityhint
