So with the recent re-examine of Sekigahara (video is based on out-dated knowledge), we're 100% sure Shimazu Yoshihiro didn't betray anyone, and it's possible Kikkawa Hiroie also didn't (though not for lack of trying, it's possible he didn't get a chance to).

Of the three men:

1. Shimazu Yoshihiro was forced into retirement and the position was passed to his son, but otherwise the Shimazu clan was unpunished.
2. Kikkawa Hiroie had hoped the Mōri clan (Kikkawa was a Mōri branch) would come out of the war unscathed. Instead Tokugawa Ieyasu found reason to punish the Mōri and ended up taking about 3/4 of the Mōri land. Kikkawa Hiroie was therefore assigned a plot of the Mōri's new domain, which was also about 1/4 of what he had before.
3. Kobayakawa Hideaki, for his decisive part in winning the battle, was greatly rewarded with Okayama domain. He then died two years later from drinking too much (though it seems he was already a drunk before Sekigahara). As he had no offspring, the clan ended and most of Okayama domain was given to the Ikeda. Whether this counts as consequences is up to you.

Of the two other confirmed traitors in the main battle:

1. Ogawa Suketada had his domain added to Tōdō Takatora's. Suketada was not given a new domain, officially because "he always abandons the weak and follow the strong." However his son was immediately given a small fief elsewhere, so the punishment was de facto decrease and not confiscation. His son died without an heir in 1610 and this new fief was then confiscated.
2. Wakizaka Yasuharu seem to have been pro-Tokugawa but forced by circumstances to be on Ishida's side prior to the battle, so afterwards was unpunished. His fief was increased and moved in 1609. The clan was moved around a few more times before settling in a corner of Harima where it remained.