I don't know what this bracket style is called but read
It would be like IIHF WC brackets, but little bit different or same if you want.
First there would be a round robin stage (2-4 groups).
Then (if 2 groups) 4 teams continue to next stage where A1 faces B2 and B1 faces A2. Winners play in finals. Losers do bronze match.
(if 4 groups) 3 winners of each group continue (12 teams) to the qualifying round. The qualifying round is another round of group play with two groups of six, with the top four teams in each group advancing into the knockout playoff stage. The bottom four teams in the preliminary round played in another group as well; this group determined relegation.