Hi @Maarten Delissen
According to our research, there is no way to add the same Word DotX template to all teams in your company at once.
If you would like this feature to be added, please submit feedback in Microsoft Feedback. Many features of our current products are designed and upgraded based on customers’ feedback. With requirements like this increase, the problem may well be released in the future.
The currently feasible method is to manually add the template to the required teams. Or you can try the method mentioned in this post to see if creating a new SharePoint document library can help you.
Thanks for your understanding and support.
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