"iirc" - shorthand for "If I Recall Correctly" ;)

Rosetta is a x86 architecture emulator installed on Macs with ARM architecture. It is used to run programs that doesn't support the new Mac architecture (IDB companion is one of them).

If you don't have a mac with ARM (currently M1/M1 Pro/M1 Max processor), you don't have to care about rosetta.

Try googling your error, I reckon there are some posts about the same issue as yours.