Seems like there is at least a bit of interest [1] to convert lirc definitions [2], which is great, because there are so many of them. There even is a definition for my about 30 years old hifi! A really nice hack I saw is to send the code via something that reads lirc and capture it with a flipper in learning mode [3].

[1] https://forum.flipper.net/t/is-possible-to-convert-irplus-fi...

[2] https://lirc.sourceforge.net/remotes/

[3] https://github.com/Lucaslhm/Flipper-IRDB/pull/294