mps-youtube (terminal-only): https://github.com/mps-youtube/mps-youtube
youtube-viewer: https://github.com/trizen/youtube-viewer
FreeTube (which uses the invidious API): https://github.com/FreeTubeApp/FreeTube
youtube-local (my project): https://github.com/user234683/youtube-local
smtube: https://www.smtube.org/
Minitube: https://flavio.tordini.org/minitube, https://github.com/flaviotordini/minitube