In Magento 1 from admin under Manage Customer section we can update/change the customer new password easily but when it comes to Magento 2 that option removed by Magento.As we are migrating customer from Magento 1 to Magento 2 or want to change password of existing customer
For an easy way to change the password for bulk of customer in Magento 2, you can import customer CSV file data of existing customer email id and password field. You can give your password which you want to change and password_hash should be blank.
Please refer the below sceenshots:
