How create entirly in blueprints or c++ a multiplayer chat system but no buy it on marketplace.
Marketplace assets have been created for ease of use and to save time creating the systems behind them. There’s plenty of documentation of replication, Which would be perfect to recreate the multiplayer chat system:
As an alternative, Feel free to use the Unreal Engine 4 documentation
There’s no be all and end all guide to quickly creating a chat system, If there was, Then what would be the need for the Marketplace assets? The marketplace is a great place to support not only creators but to help you take your projects to the next level.
If you’re hoping for a quick plug and play system… Yeah, You’re not going to be able to avoid using the Marketplace asset; As these assets are updated with every engine version; You can feel safe in the knowledge that you’ll not have to deal with an outdated tutorial / outdated content.