All 4 of your requirements can be achieved in Freshdesk. I've raised a ticket for you so that we can give you in-depth assistance. Do write to us if you have more questions.
about 1 year ago
Freshdesk supports remote authentication through which users can login using their website or application login credentials. You can integrate your SSO provider with Freshdesk to provide a seamless login experience. To know how the remote auth works in Freshdesk, please read this article.