Anyone who has played anything competitive will tell you that the Swiss format is the best tournament format. I really think it is as well. However, I don't necessarily think it is the best for football.
I'm unsure how they are going to structure this, particularly the draws for each round. The first round of group matches will probably be seeded to some extent, just like has been previously. Maybe some kind of restriction on playing a team from the same country too, but after that I think it would be anyone can play anyone.
Normally, you'd tend to play someone who has the same record as you, but you could also be paired up or down (vs a player/team with a better current record than yourself). So, for example, Arsenal beats Atletico and Barcelona beats Bayern in the first round. Arsenal & Barcelona are 1-0 and could face each other in round two. Atletico & Bayern are 0-1 so could face each other. If ties are allowed it becomes slightly trickier to always play someone on the same score..
My main worry with the Swiss format in the way that I'm used to it is, that you don't know your next opponent until all games are completed and the next round is drawn. This isn't really an issue in itself, but in European football in particular, this method would be very hard to structure. It hurts the clubs and fans in terms of arranging travel and/or accommodation in advance to be able to get cheaper deals.
Hopefully, they have a good way to organize it. Perhaps they will just draw all the games at the start like a domestic league and I missed that part? But that just seems even more awkward to me.
Either way, I like the format as it is essentially just a league with playoffs, but I don't quite like it for football as I do other things, like chess and video games where everyone is just there in the venue for the day/weekend.