A PEO is a Professional Employer Organization. PEOs enter into a co-employer relationship with clients, which allows them to share and manage many employer-related liabilities and responsibilities. Companies outsource their human resources to the PEO while maintaining all the other operational aspects of the company. The PEO provides human resources services, employee benefits, and payroll administration.
When you utilize a PEO type service in another country (outside your home country) and you do not have an entity, you are not entering into a co-employer relationship (since you do not have an entity set up). In this case you would be using what is called an Employer of Record (EOR).