Hello,
All states require domicile certificate for state counselling. In neet pg, you can apply for state counselling in either the state of your domicile or the state of your mds college.
However to apply to state colleges without domicile you can check these options:
50%of the state government seats are under all India quota counselling. You can apply for these seats.
All private colleges allow students of other states to apply for private and management seats in their colleges.
For deemed universities in a state you can apply through deemed university counselling. You do not need state quota
So, if you want to apply to a non domicile state you can apply to these categories of seats.
Hope this helps.
All the best