What are Applications?
It’s a simple Message to the Guild with the wish to get into the Guild.
The Guild Members with the Permission HandlePlayerApplications can accept or deny the Application.
If they accept, the Player will join the Guild.
Important: A Player can only applicate for a Guild if following:
If the Player has not send already an Application to the same Guild.
The Guild did not exceed the Max Member Count.
If the Guild allows Applications.
If Applications are enabled.
1. First of all, we have to enable Applications for all Guilds.
Go to your Player BP and open the Details Panel of the Guild Component.
Set the Variable Allow Applications to true.

2. Open the Game State and open the Details Panel of the Game State Guild Component.
Set the Variable Max Visible Applications to your desired Value.

In this example if the Application Count of one Guild exceeds 10, the oldest will get denied.
For example if current 10 Player are Applicating for Guild X and another Player is making an Application, the oldest will get denied.
If you set the Value to 0, no Applications will get denied.
Now every Member of a Guild with the Permission HandleApplications can call SetAllowApplications, which enables or disables Applications for the Guild.
If the Applications are enabled other Players can call ApplicateForGuild to applicate for it.
The Guild who get’s the Applications can call SetApplication do accept or deny them.
Look into SP8_WBP_Guild inside the Directory RPG_Essentials / Example / Widgets to see how the Guild Widget could be made.