I would say
1-4th(1st seeds, higher placement of a region at last year's champs, e.g. Leviatan Wins this year, Americas number 1 team gets the number 1 overall slot next year no matter who that is)
5-8th, 9-12th, 13-16th ranked in same way ( highest placed region to lowest)
Then you get 1v16 2v15 and all the way down in round 1
same for round 2
but in round 3 this coefficient goes into work. This coefficient equals opponent Wins-opponent Losses
Let's say you have 4 teams in the 0-2 pool, ranked 6th, 8th, 12th, 15th overall
We rank them based on their opponents, not seeding:
Number 6 played against two teams who are currently 2-0 and 1-1, giving their opponents an overall score of 3-1 and +2
number 8 played against teams who are 1-1 and 1-1, giving them +-0
number 12 played against teams who are 1-1 and 0-2 giving them -2
number 16 played against teams who are 1-1 and 1-1, giving them 0
If you rank by seeding, 6 plays 16, and 8 plays 12, but 12 faced weaker teams based on the event results, so it really isn't fair
Buccholz would pit 6 vs 12 and 8 vs 16 because 6 faced the strongest possible teams and 12 faced the worst possible teams.
I hope I understood it clearly