What is the new rule about 20 visa Chang to 18

You cannot change your visa from 20 to 18. The only chance for you is to cancel your 20th visa, exit Kuwait and return with an 18 visa.
permits may be transferred one year after the date of issuance of the work permit of the migrant worker. There are two prerequisites for allowing the first transfer to be approved by the original sponsor who hired the worker, and the second is that the expatriate's residence must be transferred to a new sponsor who has the same activity. It only has to be transferred to another farm and thus for grazing, fishing, and cooperatives.