The Twins have a glut of DH bats who are listed as outfielders. Larnach is having a better season than most believed he would produce, so he leads the list because he could bring back something worth a roster spot. Abreu would be #1 in the Twins bullpen.
It really isn't about liking Larnach, it is about finding some balance with the roster. Wallner, Mendez, and Gonzalez are DH bats. Roden and Rodriguez are questions, both LH bats. Martin has some utility and Fedko had a rough intro to MLB. Jenkins is waiting for a shot. Keaschall is unlikely to play on the dirt again. Buxton has a contract. That is eleven outfielders, not counting Kody Clemens or Ryan Kreidler who can both play out on the grass.
So 13 guys is a lot. Somehow this piled up on the Twins and eventually the numbers will need to be sheared down. The biggest problem with the list is that only Jenkins projects as a talent to lean on, although Buck will still be around too. So if one deletes Clemens and Kreidler and looks over the eleven names it seems like Buck and Jenkins are keepers and then pick two more. However one looks at it there needs to be a trade of an outfielder or three. Larnach seems like he has the most value. Send Wallner somewhere where he might get another chance as a favor.