It is possible(any guide) to login and create user in sphinx using webcore without using TSphinxWebLogin.
I want to hide the create user option by creating my own login page and also if possible to have a internal webapp to create users(with default password and force to change it in next login), users will not be able to autocreate accounts.
There is no such built-in option for now. You would have to create your own API server that, server-side, would use the direct Sphinx classes and methods to create users.