When I run the Create mod on a server, it tells everyone who tries to join (Incomplete set of tags received. Please contact server operator)

I have the issue to.

I also have this issue

Same here, i can't play your beautiful mod with my friends :(

Figured it out:
Download Java 11.0 from adoptopenJDK, rename your forge jar to server.jar, navigate to it in the command line with cd filepath. I'm storing my server folder in MacOSXUser/Library/MinecraftServer, so I would put in cd Library/MinecraftServer
Rename the Forge .jar file to server.jar (So you can run it easily), and then type in the following:
export JAVA_HOME=`/usr/libexec/java_home -v 11.0`
Next, put in
java -jar server.jar
This worked on MacOS with MC 1.16.4 and latest Create version. If it doesn't work, send me the log from loading the server through Github Gist