The U.S. affiliate files Form I-129 and pays the USCIS fees listed in the current G-1055 schedule, including the fraud-prevention and asylum-program fees and optional premium processing. The relocation package, taxes and translations are separate matters.
The petitioner's costs and the employee's costs are different lists
Because the affiliate is the petitioner, the government fees are its expense: the base Form I-129 fee, the fraud prevention and detection fee, the asylum program fee and premium processing if chosen, all at the amounts in the USCIS fee schedule in force on the filing date. This site does not quote figures because they change; consult Form G-1055 directly. The affiliate should also budget the professional preparation of an evidence-heavy file and certified translations of French manuals and training records.
The employee's list is different and is not an immigration cost at all: moving expenses, housing during the assignment, and the tax consequences of eighteen months of U.S. residence, which a cross-border tax adviser should review before the family commits. Nothing in the classification requires the employee to reimburse petition fees, and an employer that wants such a clause should take separate employment-law advice.