A few of the top Asian countries do not enforce a strict foreign player rule in their domestic leagues...
The Asian Football Confederation's (AFC) club tournaments allow its participants to field a maximum of four foreign players in a matchday squad and it is a mandatory requirement that at least one of those four has to be an Asian footballer (from AFC member nations).
While most leagues in Asia follow the 3+1 rule, there are some countries who have become exceptions to this guideline. The likes of Japan, Australia and the Arab countries couldn't care less about the reduced number of local players playing at clubs due to the lack of strict regulation on foreign players.