When "Device Language" is specified in MagicPod's test execution settings, although the language of the entire device is switched in the iOS simulator, only the app being tested is switched in the real iOS device. In this case, nearly all of the app’s display language will be switched; however, some messages displayed by the system, such as permission confirmation dialog boxes, shall remain in the original language.
If the real device is at hand, you can avoid the problem by changing the device language settings in advance. However, in the case of SauceLabs or BrowserStack, this kind of system message will always be displayed in English. In case this problem must be resolved on SauceLabs or BrowserStack, it will be necessary to automate the operation to change the language on the settings app with MagicPod.