Anti World Fly

Most similar plugins just block the /fly command in game and can easily be tricked. With Anti World Fly, no more hassle, prevent users from flying in a world or typing specific commands no matter how hard they try!

Documentation
Feature requests, support and issues
Plugin translations
Source code

• Specify the blocked worlds in which the plugin operates (will NOT affect other worlds)
• Disable /fly, /efly and /essentials:fly commands in blocked worlds
• Disable any additional commands you specify in the config
• Disable flying when entering blocked worlds
• Disable flying when connecting to blocked worlds
• Disable flying in blocked Creative worlds
• Disable flying when changing to Creative mode in blocked worlds (optional)
• Re-enable flying when switching back to a world where a player is allowed to fly (optional)
• Display screen titles when entering a blocked world (optional)
• Display chat message when entering a blocked world (optional)
• Easy to use commands, user-friendly interface
• Language file to modify all displayed texts; 5 available translations
• In game or console commands
• Very lightweight and efficient plugin, no dependencies
• Compatible with any Minecraft version from 1.7.9 to 1.21.4
• Open-source
  

You can get support by opening an issue on the project's GitHub page here. I rarely check the comments here, so GitHub is the best place to get support!