Youtube Videos have an aspect-ratio of 16:9, Shorts have 9:16.
- Insert a Video element,
- add your YouTube Short ID (Shorts URL doesn’t work correctly in Bricks 1.12.4!),
- set Style > Layout > Aspect ratio: 9/16
Unfortunately, there’s no automatic detection, so it’ll be a bit difficult to adapt that dynamically in a loop.
For the Shorts URL issue, see
WAIT: Video element doesn’t detect YouTube Shorts URL correctly