[1.16.5] WorldGuard Flag deny-spawn entity

[MaxifeuxG]

Is your feature request related to a problem? Please describe.
I have a problem with the Worldguard plugin I would like to control the spawn of entities in a region (spawn) but it does not understand but mod entities

Describe the solution you'd like
add a worldguard patch so that worldguard includes mod entities or added it to the Worldedit patch

Describe alternatives you've considered
I have no alternative mod mobs spawn in the region

Additional context
on the plugin documentation the devs don't want to do anything because they don't like hybrid servers

[Kotori0629]

I don't understand, what command should I use to set the flag?

[MaxifeuxG]

/rg flag [name of your region] deny-spawn monsterforge:entity,Minecraft:spider