Thanks for reaching us. I'd like to inform you that the video resize feature on Adobe Express web. Users can change video size per templates available or as per their requirements.
Moreover, if users work on an iOS mobile device (iPhone or iPad), they get the ability to upload a video from the device to Adobe express & then work on it. Template sizes for different social media platforms are available, including IG stories.
The workflow mentioned is how Adobe Express currently operates; as this release is just the beginning, we welcome your feedback in building this new app together!