I don't think that's possible, but I don't have a ton of experience with the mobile app. BTW this is a user forum, and not a way of reaching Cyberlink customer service or tech support.
One thing you can do is to produce your 16:9 project as-is, and then start a new 1:1 project and import the produced 16:9 vid and crop it. That way, you'll have identical content in both rectangular and square versions.
YouTube/optodata
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