Hi @wws9,
Hi @jaohsu, if you have a system level ROS2 Humble/Foxy install, as you long as you source the install in your bashrc or in the terminal before starting through the launcher or running isaac-sim.sh or ./python.sh from the terminal, you should be able to access all your ROS packages installed on your system from Isaac Sim.
What @jaohsu mentioned is recommended when you don’t have any system level ROS install and therefore have to use the libraries shipped with Isaac Sim.