My own personal pick since I'm not involved with the championship: Taking 49ers by 10. Chiefs have the advantage at QB and their receivers are better, but the 49ers' defense matches up favorably imo and SF is more talented everywhere else. 9ers have up second fewest yards in the season, fewest yards per play, and ranked in the top 10 in both points and turnovers forced. 49ers also gave up the fewest passing yards. Two very strong units on the field when KC has the ball.
However, when SF has the ball, it feels like a substantial mismatch in favor of the Niners. The 49er offense, while not as imposing as their defense, is still very good and highly underrated. Fourth in yards, fifth in Y/P, 2nd in points. Perhaps especially important, extremely good at running ball, with the second most rushing yards in the league, which is notable because the Chiefs' defense sucks at stopping the run (26th in rush yards allowed overall, 29th in yards allowed per rush). The Chiefs mediocre defense is a weakness that both Houston and Tennessee exploited for a while, but each team was respectively undone when Bill O'Brien lost his mind at the end of the first quarter and when KC realized that they could just load the box against Henry and Tennessee could only do so much with a meme at QB. Jimmy Garoppolo is capable of consistently picking apart single coverage if he has to, and can win the game if Kansas City essentially dares him to.
I respect Mahomes/Hill/Watkins too much to think it'll be a massive blowout, but I do see SF comfortably winning.