I'm genuinely lost reading your comment as neither the p nor the i are silent in pissed (/pɪst/). The only weird part is the "ed" pronounced "t" but that's fairly common in English.
I also don't get the part about "ps" in romance languages. There is no special pronunciation rule regarding this group of letters in French. Are you sure it's not specific to Italian?
Edit: I think I now realized you might be talking about the pronunciation of words like pseudo and psyched where the p would indeed be pronunced where it French (and I guess in the same way in Italian).
For gn we have ñ, so we're not tempted to interpret it a la francesa.
But we do have the same problem as Italians with "pseudo": the "p" is right there, why are you skipping it?!? :-p
Wait, they're skipping it?! Now that you mentioned it I think you're quite right, I don't remember hearing that many "p"s in front of "seudo".
I'm originally Italian and my English is now quite good. A very, very common mistake among most "mediterranean" and "romance languages" (Spanish, Italian, Portuguese, French, Romanian) people when speaking English is to pronounce ps as in "pissed" without the "i", instead of just the "s" (the "p" is silent), which is the correct way to pronounce it in English.
Another very common mistake in my language group is the "gn", as in signal.
Correct English is sig-nal [0], while my group usually says it with a different "gn" sound [1].
Well, there's much more, of course, but I wanted to share these two just because, anecdotally, I hear the mistake very often.
[0]: https://www.youtube.com/watch?v=whOXnmbOJvQ
[1]: https://forvo.com/word/segnale/