Take a close look at BoxLegend2. It can be intepreted as a chrysalis stage. The inner, metamorphing, slumbering legendary has no visible eyelashes or mouth.
The upper line is blue like Solgaleo's eyes, the lower line is red like Lunala's eyes.
Felinoids in general sleep with their bodies upright, hence the blue is on top. That way, we can intepret that the creature is upright.
Bats sleep upside down, hence the red is below. That way, we can intepret that the creature is upside down.
>>29351632
OP here. In addition to this, Solgaleo has a red mouth and red 'pieces'. Lunala has a blue 'stomach' corresponding to the blue line.
Actually it'd be interesting if Solgaleo and Lunaala were the third stage of this line being the first evolving legendaries as well as another split evo probably based on time of day, or in this case game version. The bottom one looks like both sun and moon representations, as the left and right have crescent shapes and the other parts the sun rays.
I just think its like, a weakened state they're probably meant to be in when not, y'know, active. Just instead of being purely plot ('dead' ho-oh, stone Groudon/Kyogre, etc) they're also pokemon.
Probably gonna come up in the plot, one of them is inside lillies bag because Ultra beasts/the other one/marshadow/skull/aether/Arceus/etc kicked its ass back to such a state.
>>29351632
IT'S A CHRYSALIS! you can clearly see cloudmon inside chrysalismon