Spotlight

Curated Sequence

The last step before a set goes out. Finished pictures and clips, put in the order you want them seen and exported at one ratio, numbered.

One of the tools in Aspects for macOS. $19 once, cloud optional.

One ratio for the set: Every frame leaves at the same aspect ratio, which is what a carousel requires and what it silently crops for you when you get it wrong.
Numbered in the order you set: Zero padded, because an upload picker sorts by name: an unpadded set becomes alphabetical order at the moment of posting.
Stills and clips together: Each comes out in its own medium at the shared size, so a carousel of photographs with one video in it is a single press.
Reorder by dragging: A sequence is the order, so the order is the thing you edit. Cells carry their own files and nothing on disk is renamed when you move one.
Shared treatment: One fit, one background, one set of effects across the whole run, so the set reads as a set rather than as a folder of separate exports.
Output size: Thirteen ratio presets or a custom W by H, with the same six image formats and quality control the other tools use.