Microsoft project management software used to plan, manage, and communicate a project schedule and other information among workgroup members, project managers, and other stakeholders.
Dear MatsuzakiJM,
Good day!!
I understand your requirement but I am sorry to convey that the feature of exporting to MPP file is not available in the Project for the web and I agree with you of having this feature in the Project for the web will help many users and I have added the idea as a feedback in the Project Feedback Forum, please add your valuable vote to the idea: https://feedbackportal.microsoft.com/feedback/idea/523ec44f-afe9-ed11-a81c-000d3ad924d4
As a workaround, yes, we can use the Power Automate for exporting the data to MPP file automatically but since it requires the customization of flow, I suggest you to post your concern in the Power Automate Community: https://powerusers.microsoft.com/t5/Microsoft-Power-Automate/ct-p/MPACommunity to get the detailed flow from the experts.
In future you have any further concerns on Microsoft 365 Services, please feel free to open a new thread in this community and we will try our best to assist you.
Thanks for your patience and understanding. Have a good day!!
Best Regards,
Sophia