James Karinchak
This one is a bit of a bummer as it wasn't that long ago that it looked like the Guardians had found yet another diamond in the rough in James Karinchak. The walks were certainly concerning most of the time, but two seasons of a sub-3 ERA with the number of strikeouts he was putting up was legitimately exciting. If he could just cut down on the walks, you would be looking at one of the elite bullpen arms in all of baseball.
Unfortunately, 2023 has not gone to plan for Karinchak. His walk rate actually got worse this season somehow at 6.18 BB/9 and he struggled to put away batters. Things got so rough that the Guardians had to send down to the minor leagues again in the hopes that he could at least learn to command his stuff well enough that he could make it through an inning of relief without throwing a ton of pitches. For the moment, the jury is still out as to whether or not Karinchak is making real progress and the longer he sits at Triple-A, the less optimism there should be.
Oscar Gonzalez
It is tough to get singled out as being particularly bad at the plate on this Guardians roster full of guys who have struggled, but Oscar Gonzalez has managed to pull it off in 2023. In 133 plate appearances this season, Gonzalez has posted a 65 wRC+ and -0.7 fWAR which is actually kinda hard to do in only 133 plate appearances. The defensive metrics have not liked him in the outfield, either, which certainly isn't helping matters.
However, there is a bright side with Gonzalez in that he has played much better in the second half of the season so far with a 109 wRC+ and hopefully that is a sign of him turning things around. However, his walk rate (or total lack thereof anyways), offensive inconsistency, and lack of defensive value probably means that the Guardians should be looking to upgrade his roster spot unless he really puts on a show the rest of the 2023 season.