Hongo has options not only to enable/disable related post globally but also to set it on post/portfolio level.
Enable/disable related post globally for whole website.
Please refer this article for more information: Theme Customizer > Layout and content > Post Single.
Enable/disable related post single post wise.
Step 1: Go to WordPress Admin > Posts > Add/Edit Post.
Step 2: Hongo Post Settings > Single Post Settings > Related post section. See below image for more information.