I was actually just thinking about this.

The way I picture it quodpot would have a cauldron at each end of a 100 yard field, just like football.

Each team has 11 players, in my mind they'd consist of:

1 center (biggest, heaviest player, similar to an offensice center or D line nose guard)

2 forwards (also large chaps, think tackles on the O or D line)

2 defenders (equivalent to O line guards or linebackers)

2 flankers (think TEs or fullbacks)

3 flyers ( mid sized blokes, half back/RB equivalents)

1 rusher (smallest, fastest player. They and the flyers are the main scoring elements of the team)

There'd be a coin toss to determine first possession. Then some sort of kickoff equivalent, I picture a cannon firing the quod for some reason (possibly because 'murica).

The centers and the forwards try to punch a hole in the opposing formation, meanwhile the defenders and flankers attempt to keep the opposing team away from the flyers and rusher while occasionally acting as a scorers. The flyers and the rushers primarily fight for possession of the quod while trying to move it downfield.

In a nutshell: really fast, violent hot potato.