MarsSeed [1] filed a deletion request for ros-noetic-tf-conversions [2]: Fails to build. Unused, obsolete orphan from 2020.
Only the non-EOL "ros2-*" AUR packages are compatible with Arch Linux. ROS1/Noetic is based on Python 3.9, Qt 5.12, CMake 3 and the EOL Ubuntu 20.04. [1] https://aur.archlinux.org/account/MarsSeed/ [2] https://aur.archlinux.org/pkgbase/ros-noetic-tf-conversions/