FURN is a React Native based component library, so there will be a few differences in props and behaviors if you are porting components from FluentUI.
onClickisonPressaria-labelisaccessibilityLabelaria-hiddenisaccessibleset to falsearia-descriptionhas no direct equivalent, useaccessibilityHintto give more detail on what happens when an action is invoked on a component
CSS is not available in React Native, so styling must be applied to elements directly instead of using classNames or other selectors. A good way to ensure that styles are passed through a tree is to use a ThemeProvider. More information about our theming can be found here