You could try forcing user data to be regnerated and see if that works.
I would start by renaming the .\PortableApps\LibreOfficePortable\Data\ folder and then start LibreOffice again. This should force LibreOffice to regenerate the Data folder. Be aware if you do this it will wipe you user data for LibeOffice Portable.
Also note that LibeOffice Portable will share the same Shared Python sitepackages as a Installed version Of LibreOffice uses.
If you can get LibreOffice started and use the APSO extension, in the console, you can find the Python paths a follows.
import sys
import pprint
pprint.pprint(sys.path)
I would think that any shared python path would be very unlikely to be creating an issue.