If you mean add it to an existing file, possibly
loffice -o [filename] [script]
I guess the [script] bit because that is how I routinely opened Supercalc files in order to add data in the 80s.
If you mean a new file
loffice -o [filename] --infilter="CSV"
I guess "CSV" by analogy with other examples because I cannot find a list of all the command line filters.