But it has that etymological overlap with hex in the english word that means like curse or whatever and it sounds like a germanised verson of "hexbear" so I kinda like it. Big missed opportunity with Halloween having just slipped by before I came across this word
Sechseckiger Bär would be the correct translation for hexagonal bear.
Realistically, you could just translate it to "Hexbär" because German also has the "hex-" prefix to indicate the number six. Otherwise I'd also go with "Sechsbär."
With regards to what @ReadFanon@hexbear.net said: In English, witches hex stuff. If a witch hexes a bear, it is now a hexed bear. That doesn't work quite as well in German because while the word for witch is Hexe, the verb is "verhexen". So instead of "a hexed bear", you end up with "ein verhexter Bär."