Chris Lanphear

A very simple plugin to disable the Block Editor (formerly known as Gutenberg) and restore the classic WordPress editing experience. 
There are no settings. If Guten-bye is active, the Block Editor will be disabled for all registered post types and the original 
“Classic” editor will be used in its place.

Gutenbye

A very simple plugin to disable the Block Editor (formerly known as Gutenberg) and restore the classic WordPress editing experience.

Samuel Wood (Otto)

Replace the smilies with the original versions from previous versions of WordPress.
Added bonus: Disables all “emoji” functionality in WordPress 4.2 and above.

Classic Smilies

I have been using this plugin and I proudly recommend to everyone.
PRO
- It improve performance by removing inline JS and reducing HTTP requests.
Cons
- Smiley images shouldn't be look dull. It could be appear clear like Original.

Thanks & Regards,
Gulshan

Very goood plugin, some improvement needed

Replace the smilies with the original versions from previous versions of WordPress.

Gutenbye vs Classic Smilies