My opinion:
S: Loud, NRG, LEV
A: FURIA, 100T, SEN
B: EG, MIBR, C9
C: KRU
LOUD, NRG: I don't think I need to explain too much because they are a strong team. World Class cores
LEV: Despite their performance against NAVI not being the best, everyone in BR/LATAM knows the potential of this team, I myself considered them one of the favorites to win the LOCK IN. I think if their synergy is better they can become a very strong team, they are not as disorganized as SEN.
FURIA, 100 T: They turned out to be very strong teams. FURIA was the team that gave the most work to FNATIC in the BO3 format. 100 T was considered a solid team before and they won a few games but were stomp by Fnatic
SEN: The core of this team is very strong, probably S-level, but the team was very disorganized. I believe they can do better, so I'll put it in A for potential
EG: It was never a favorite, but it proved to be a consistent team winning some games in LOCK IN
MIBR: They were never favorites either, but they already had a Core before the franchises and lost to Talon, a strong team that EG also lost
C9: They used to be an S/A level team, but losing their best player and the IGL a month before the championship, and not knowing the replacements is reason enough to put them here.
KRU: They were no longer one of the favorites and a month before the start of the championship, they kicked Xand from the team, who was the best player until then (even though Keznit is better, nagz and klaus are much worse than Xand), in addition to changing the whole Coach Staff.