Moreno and Sandoval are both nominative. If either gets injured and cannot compete, Mexico loses the spot, they cannot reassign it to whomever. Then FIG would reallocate it to the next gymnast in line in the AA and UB respectively.
The Mexico +1 earned by the team is non-nominative and can be issued to any gymnast Mexico chooses.
Same goes for Germany and South Korea. The two nominative spots cannot be redistributed within the federation.
So for Germany, Voss and Schafer are locked.
Germany will have the difficulty of naming the 3rd athlete. Seitz would be the most sensible pick should she be healthy due to medal potential on bars. But also Malewski is another gymnast with medal potential on beam. In the AA Helen Keveric is eligible to compete senior next year, so she might be an option.
Unfortunate for Germany that they just missed qualifying.
A team of Voss, Keveric, Malewski, Seitz, Schafer would likely make team finals in Paris and as a result would be a medal contender.
Crazy that we are in the day and age with WAG that if you qualify to team finals you CAN win a medal. Last three Worlds the 8th place team, just barely qualifying ended up with the team bronze!