This is a good shot and show as to what i think a Siberian/Alaskan Pokemon region would be like. Now im no graphic designer, so this aint gonna be very detailed. However people should be able to figure out 3 major things.
1- The white colored stuff is snow and permafrost, i am exaggerating these traits to make it feel more like a Pokemon region. In reality if you go up to Barrow, Alaska you will find some patches of snow mixed in with a
majority of the ground being hard dirt and pockmarked with little ponds of nearly frozen water. The water around Barrow isn't exactly frozen either. You could swim a ways before touching ice, tough you might want 2 layers of blubber.
2- There are no routes between some of the cities, but instead dashed lines. Those dashed/dotted lines are representing railroads and ships. I wanted to make this truly feel like it was an isolated region, and what better way than by splitting the region into four smaller sub-regions. I shall name them off in a bit. Oh, but fan fact actually, Juneau the capitol of Alaska has no roads going to or through it. So the only way to get to Juneau is by water or by air, so I decided to leave it off the map.
3- I lied about 3 things I just wanted to see if you'd come to see what the 3rd thing was here.
Anyways, The Beringia Region is made up of The State of Alaska, Chuktoka Autonomous Okrug, and Kamchatka Krai. Ice-type Pokemon would be very common here. However lots of Flying, Rock, Ground, and Ghost-type Pokemon would be pretty common finds here. Why would Ghost-types be common here? Well let me educate you on some people known as the Inuits. The Inuits lived in Alaska and Siberia. They were divided into different groups like the Sibirs and Aleuts. However when Russia came along to colonize the place a few diseases and people cut down some Inuits settlements and forced them to move further up North to places like Barrow and the Aleuts. Some places like Anchorage and Leningradsky up towards Wrangel Island were settled by Americans and Russians. I would speculate that as the Inuits dwindled in population their spirits became stuck in limbo or purgatory and now roam the lands as angry Ghost-types.
Now there are 4 sub-regions in the region. From East to West like an Arabic book we shall go. The Anchorage Sub-Region, the most populous of the 4 it is what many trainers and people see of the region. Stretching from Kodiak Island to Barrow it is one of the most beautiful places to see. Further West we stumble onto the Diomede Sub-Region This region is known as the "Heart of Beringia" as at one ancient point the two halves were connected. However now they are connected once more by the "Great Diomede Bridge" Spanning from Tin City to Naukan it is one of the longest and largest bridges built by humans and Pokemon. Past Kodiak and further South than St. Lawrence Island is the smallest of the 4; The Aleut sub-region. The Aleut sub-region whilst sparsely populated with its biggest city being Unalaska, rolling in at over 4,400 people. The next 2 settlements are; Adak with 329 people, and Navy Town as a small military base. However this region is pockmarked with Inuit ruin and banged up old military stations like Attu Station just West of Navy Town. The final and most Western region is the Kamchatka region with its industrial cities on the Proliv Like with the exception of Ust-Kamchatsky, the capital. On the Bering Island between these cities you will find Victory Road and the Pokemon League. It is the warmest and most industrial of the regions producing much of the regions wood as well as being a stopping point for many ships.
I have a little bit of lore for this region and it goes a little bit like this; When it was discovered by explorers people weren't to keen on moving there, until someone found gold and oil in the modern day Anchorage and Diomede sub-regions. The population started booming and eventually the original people of the land were pushed further up North and some towards the Aleutians. Eventually the separate halves of the Beringia region went to war over the Diomede islands and resources on them, as someone had discovered gold on them and both sides wanted the islands. The war was brutal but very limited. Thanks to the spread out population centers and weather the war eventually stopped 2 years after it started. Now 50 years later after much recovery the two halves finally united after the completion of the Diomede Bridge. Now the two, now united regions work together and help one another survive the brutal winters and stupid tourists.