Opencart 3.x new version contains the following new features.
MarketPlace:-
OpenCart 3.x version newly includes extension “Marketplace”. Store owner can download and purchase OpenCart extension directly from the administration area.
Menu : Extensions -> Marketplace
The extensions come with two mode OCMOD and VQMOD. Custom installation procedures with all document to come with purchased extension.
But, Opencart 2.x version doesn’t contains the Marketplace features
Translations:-
Language Translation is new feature in the OpenCart 3.0. Now, Translation used for Crowdin Project. Nearly 45 main languages translate support. Please check the languages Crowdin project link.
But, Opencart 2.x version doesn’t contain the language translation features.
Theme Editor:-
Theme editor feature is available in the Design Menu. Now, We can edit the store’s file code through admin panel as well
Choose Store: Here choose the store and edit the store files in admin panel
Design ->Theme Editor ->choose Store -> choose Template
Language Editor:-
Language editor feature is available in the Design Menu. Now, We can edit the default languages in this section
Design ->Language Editor