Conversion from Gazebo topic to MAVLink message


I am having difficulties to understand, how can I create gazebo plugin, that transform Gazebo’s topic from sensor to MAVLink message. I am kinda lost in the whole folder management of px4-Autopilot. There must be any preconfigured plugins, that I can just adjust, right? I am using ros2 branch of px4-autopilot.
If you could provide me any information, I would be glad.

Thank you, guys.