Sorry but I think I didn't fully understand your situation. If you embedded PowerApps in Dynamics 365 CE on tenant1, then your users need to have user account from tenant1 to access it.
After you have embedded a PowerApp on a page and confirmed that it is working correctly with any data context passed from the page, you might want to share this embedded PowerApp with other users in the system. This can be accomplished in two different ways using the personalization capabilities of the product:
The recommended scenario is through the system administrator, who can push a personalization to all users or a subset of users.
Alternatively, you can export your page's personalizations, send them to one or more users, and have each of those users import those changes. The Manage option on the personalization toolbar enables you to export and import personalizations.
Community Support Team _ Mona Li If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.