Hello.
A business owner who has two or more businesses cannot transfer a worker from one business to another, even if they have exactly the same activity, unless the business is registered for the hiring of workers, otherwise he will be fined €12,000. However, if the two companies were one, the HRA and collective agreements allow the company to make such a transfer under certain conditions. This makes it difficult for micro and small related (same owner) companies to operate during holidays or sick leave, and instead of employees being optimally deployed, they are overworked in some places and may not have enough to do in others. The only option under today's legislation is to employ an employee in a related company for a week under the same conditions and then re-employ him or her again, which is of course not an option, especially if it is a sickness replacement where quick action is needed. But probably some more annoying inspector will also want the worker to have a medical check-up before each new job, and so on.
I suggest that this should be allowed to be arranged in a more company-friendly way and that the duration should be limited to a certain number of working days per year.