I will beg my ignorance as to what is done in a psychiatric ICU. If you have skills with rapid physical assessment, management of multiple IV lines, titration of hemodynamically active continuous drips, advanced cardio-pulmonary resus skills and management of invasive airways then I would could see an ED manager seeing that as comparable to ICU skills.
I believe the skills you have from what I believe happens in a psych ICU would be very valuable in the ED, but probably not considered what most consider "ICU".
So your second question is would I consider hiring you into the ED? Possibly, pysch skills are great, but if you didn't have great skills in the areas I mentioned above, I would probably need to treat you largely as unexperienced until you learned the non-pysch skills.
When I went from adult telemetry to NICU, I was treated mostly as a new graduate that didn't know anything. I appreciated this. Turns out my time management and knowledge of cardiac monitors was useful but not much else.
Let me emphasize again, that if your psych ICU utilized the skills I listed in the first paragraph, I would consider those "ICU" skills and you would be at the top of the list.
If you are doing medical ICU stuff in the psych ICU, then yes, you probably have skills comparable with critical care.
If you are working in the most acute psychiatric unit that doesn't really have a intensive medical component, then you're not really doing critical care as far as nurse recruiters and managers go.
Don't get me wrong: what is done the psych ICU is very important, and lives are being saved with every bit of intensity as they are in the medical ICU. It's just not dealing as much with the medical aspect as it is the mental aspect.
Since you seem to be looking for more acute settings...why not a psych ER?
Just to ask - is psych ICU like a long term Crisis Center. I mean the acutley psychotics, suicide risks, threats to themselves, others or the environment, etc types that are spending time in an in-patient unit?