Option to cancel chat events for not global chat

[bobbyl140]

Is your feature request related to a problem? Please describe.
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I have a plugin that syncs BungeeCord chat messages to a Discord channel. The plugin provides a way to not sync messages with a prefix, which some chat plugins do for things like staffchat. But when toggling /mc and typing into chat, chat events are still sent, which this plugin of course picks up on, therefore sending staffchat to a public Discord channel.

Describe the solution you'd like
A config option to cancel chat events, preventing other plugins from getting messages in non-global channels.
As an addition, possibly also a prefix system, such as # <message> for mod chat, ! <message> for admin chat, and ? <message> for current group chat. (Should be user-configurable)

Describe alternatives you've considered
Really the only reasonable alternative here would be not having the Discord plugin. I can't just expose staffchat to everyone on Discord for obvious reasons.
As a temporary solution, I can prevent staff from toggling /mc, and requiring /mc <message> every time to prevent the chat events. But this quickly becomes tedious when repeatedly chatting in a channel.

Additional context
The other plugin is called DiscordSynthesis, available on SpigotMC. The only thing in that plugin's config that could be helpful is the ability to not sync prefixed messages, but if you're going to type a prefix every time you might as well /mc <message>.