All perfect praise be to Allah, the Lord of the worlds. I testify that there is none worthy of worship except Allah and that Muhammad, sallallahu ‘alayhi wa sallam, is His slave and Messenger.
The basic principle is that it is permissible to earn money by mediating between job seekers and employers; however, it is impermissible to mediate in unlawful jobs, and the earnings obtained through such work are unlawful. If you could start your business provided that you mediate in lawful jobs only, then this is permissible. If you would be obliged to mediate in unlawful jobs, then this is impermissible.
Allah knows best.