react-native-web/docs/guides/internationalization.md

Internationalization

To support right-to-left languages, application layout can be automatically flipped from LTR to RTL. The I18nManager API can be used to help with more fine-grained control and testing of RTL layouts.

React Native for Web provides an experimental feature to support "true left" and "true right" styles. For example, left will be flipped to right in RTL mode, but left$noI18n will not. More information is available in the Text and View documentation.

Working with icons and images

Icons and images that must match the LTR or RTL layout of the app need to be manually flipped.

Either use a transform style:

<Image
  source={...}
  style={{ transform: [{ scaleX: I18nManager.isRTL ? -1 : 1 }] }}
/>

Or replace the source asset:

import imageSourceLTR from './back.png';
import imageSourceRTL from './forward.png';

<Image
  source={I18nManager.isRTL ? imageSourceRTL : imageSourceLTR}
/>