Bytes-only rejection
If the portal only complains about **file size**, try Bulk Compress first at High Quality, then re-upload. See listing images too large to upload.
Dimension, aspect, or zoom issues
If the problem is **pixels or aspect ratio**, use Bulk Resize first to the marketplace frame, then compress. See wrong listing image size? and rejected or blurry on zoom.
Second pass
Sometimes you resize, discover the new PNG is over the cap, then compress again—that is normal for strict portals.
Throughput
For folders, prefer ZIP batches: batch vs one-file compressors.