Unfortunately being Windows only is a bit limiting... unless, are the Amiga CD32 and PlayStation versions distributed through an ISO?

Under the Revolution Editions - Shadow & Steel\Shadow and Steel_Data\StreamingAssets folder

Lure of the Temptress has hdf files, Beneath a Steel Sky is also hdf and Broken Sword & Broken Sword 2 are bin & cues.

Does this version of Beneath A Steel Sky actually have Italian voiceovers?

No. The voice is english.

It should also have French and German voices, according to the cover image scan from the Amiga CD32:

At least as of yet, you can select among English, Italian, German, and French language, at the start of a new game,
but this only affects the language of the subtitles. The voiceovers are in English.

You are given the option (also at the start of a new game) to have either subtitles only, voices only or both subtitles and voices. But even if you select voices only and you've set a language other than English, you'll still get English voices.

I am not sure if this intended or a bug.

Also, it would be nice to be able to switch between these modes (voice and text, text only, voice only) while in-game and not only from the startup screen -- but maybe that's the way the original Amiga version worked too. Still it would be a nice quality of life addition.