Can fresh Poblano peppers be used raw

Yes, they can be, but you'll want to prick each one with a sharp knife once or twice to prevent them from bursting. Once that is done, put them into a small freezer-safe storage bag, remove as much air as possible from the bag, and seal it. They keep reasonably well for about six months without tasting "burnt," but they tend to be a tad mushy upon defrosting.

I always thought the mushiness factor had to do with length of freezing time, but since you asked, I did a bit of research. Apparently, what makes chilies turn to mush actually has to do with how quickly they initially freeze:

The undesirable mushy end product that comes from freezing fruits and vegetables isn't from the act of freezing itself, but from how you freeze. Your ordinary freezer, or even deep freezer, freezes food slowly. Chilies have water in their membranes, and as they slowly freeze, it forms jagged ice crystals that pierce and puncture the membrane, so that when you defrost it, you're left with a leaky and "tenderized" result. The solution to this problem is easy … faster freezing. If the water doesn't have time to form jagged ice, you won't have a mushy membrane.

Happy Living (from which I pulled the above quotation) has an article about how to safely use dry ice to freeze chilies quickly. (I'll probably keep going the way I always have and accept the mushiness, but if you want to freeze a lot of chilies for a variety of applications, the dry-ice method looks promising.)

I'm going to say yes. In 2013 we grew 6 varieties of mild to hot peppers. On the mild side was Poblano, and on the other was an extremely hot habanero variety. As these peppers matured we would pick them, slice them, dry them on a dehydrator then deep freeze them.

At the end of the season we had around 2.5 gallons of dried, frozen peppers. They were not stored by type but all mixed together. That Christmas we ground down the 6 pepper mix into a powder, filled several spice jars and sent them to family along with our raw honey and homemade soap. This mix packed a serious punch. I use it on just about everything and we got nothing but rave reviews from those we sent it to, all folks that love spicy food.

Now in 2015, I finally used the last of the spice so I dove into the coffin freezer, pushed aside the 2014 and 2015 harvests and pulled out the last gallon of 2013 peppers. Since they had been frozen for two years I put them on a dehydrator for 24 hours then ground them up just like I had before. I'm telling you these peppers are so much hotter than the first batch it's not even funny. This coming from a guy that can drink Siracha. If you can so much as see the small red dots on your food then you put too much on. The difference between the same peppers ground up in 2013 vs 2015 is incredible.