There is no way to determine, which images with multiple variants are expanded.
When was the last time you were affected by this lack of functionality, or specific tool?
When I have 15000 images and select them for export, I might end up with 15059 for example, because I have made multiple variants on some of them; I want to export only one of them to allow automatic numbering to reflect actual count of images, but I have to manually browse all 15000 images to find these variants.
Current workaround
Are you using any workarounds or other solutions to achieve your goals in Capture One?
It is possible to mark variants with a color, then filter by this color and collapse them, but this blocks the colors for other uses - they serve only as workaround. Additionally, I have to remember when creating a new variant, that it has to be marked at the same time for the workaround to work - I miss one and I have to browse all the 15000 images anyway.
Oh yes, there is such an option ("Collapse Selected" or "Collapse All")! I was looking mostly in Browser. Checked and it works, but accidentally exposed an apparent bug with JPG images from this session's exports present on the list, even though they were never imported.
I would use the color marks or keywords for selection, that is the most practical way imo. But anyway let me see if I understand your question correctly and this is an alternative: The option you asked for does exist in the menu Image: "Show all" or "Hide all", which hides or unhides all variants of images in the selected folder or album. With all variants shown you then click, for example, on the first variant of an image with the right mouse button and choose "Select according to similarity", as a criterion you can then decide on the rating, colour marking or position of the variant and thus, for example, in the case of images with several variants, select only the first one for export.
Note: I am not working with an English version, so I do not know if the terms are translated correctly.
Oh yes, there is such an option ("Collapse Selected" or "Collapse All")! I was looking mostly in Browser. Checked and it works, but accidentally exposed an apparent bug with JPG images from this session's exports present on the list, even though they were never imported.
I would use the color marks or keywords for selection, that is the most practical way imo. But anyway let me see if I understand your question correctly and this is an alternative: The option you asked for does exist in the menu Image: "Show all" or "Hide all", which hides or unhides all variants of images in the selected folder or album. With all variants shown you then click, for example, on the first variant of an image with the right mouse button and choose "Select according to similarity", as a criterion you can then decide on the rating, colour marking or position of the variant and thus, for example, in the case of images with several variants, select only the first one for export.
Note: I am not working with an English version, so I do not know if the terms are translated correctly.