@Mattias Anders, Thanks for posting in Q&A. From your description, it is non-English. After translating, I find it seems you want to install the Whatapps twice on the managed iOS. Based on my researching, for one app, I didn't find the method to install two same apps on one device. It can only install one by default no matter if the configuration file is different.
If there's any misunderstanding, you can open case to get your local support to help on this.
https://learn.microsoft.com/en-us/mem/get-support
Thanks for your understanding.
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