Hello I noticed that Easyblog , EasyDiscus have a auto posting features for Facebook and twitter. I purchased Joocial but I am wondering do I need it ? Do I need this plugin to post to Socail Media or will the features inside of Easyblog and Disus work fine.

The autoposting feature of EasyBlog and EasyDiscuss are working fine. You can check the following documentation links on how to setup autoposting for Facebook and Twitter for both EasyBlog and EasyDiscuss:

https://stackideas.com/docs/easyblog/administrators/autoposting/facebook-autoposting
https://stackideas.com/docs/easyblog/administrators/autoposting/twitter-autoposting
https://stackideas.com/docs/easydiscuss/administrators/autoposting/facebook-application
https://stackideas.com/docs/easydiscuss/administrators/autoposting/twitter-application

Is there auto posting for EasySocial or do I need a plugin ?

Actually, we already discontinued this feature for EasySocial since Facebook announced deprecated `publish_actions` permission from their latest API.