Due to TIFF format specifications Agisoft Metashape Professional cannot save files larger than 4GB. JPG format export is limited by 65535 pixels for any side of the image.
To avoid the format limitation issues you can:
- reduce the export resolution (m/pix) to fit the format limitations,
- use "Split in blocks" feature in the Export Orthomosaic dialog,
- use BigTIFF option for TIFF format export.