I once told you already how cool it is and how happy I am for you that you were able to visit that place. Not only is it in Japan but also at the ocean, too. Double the rare and fun experience. In the same manner I feel happy that Shiny gets to accompany Rouler on a nice trip at the beach.

In regard of that Pokéball I definitely gotta say that Shiny probably won't stay in such devices for too long. He's not one of those battling Pokémon or one who likes to wait for being called out.
Now that I think of it: Pokéballs would make for quite the practical way for transporting passenger Pokémon on travels, hehehe.
Though luckily Shiny usually doesn't have it too far to reach a beach at his home city Triepeaks. Maybe Rouler also just has one of those toy Pokéballs that can bounce so nicely on the water's surface. Who knows? I have fun suggesting funny ideas as usual.

In regards of the Pokémon Trainer getup, Rouler's earpiece reminds me of those ones the Trainers use in Pokkén Tournament. It would also get for a well use in case that Rouler does use his mobile to phone back at home showing some of the nice area over the net like some internet video host.

No matter waht, I am pretty certain that they enjoyed some happy hours over at that nice place, heading for a swim, splashing around and maybe also building the one or another sand structure.
Based of the example you used it feels a little like if Shiny is watching up at something in the sky in front of him. That's not bad though as by the look of that background one can quickly assume that Shiny does simply follow one of his favourite activities, namely cloudgazing. X3

In the name of the happy lil Totodile and myself who enjoys such sweet images always, Nozo, thanks for the chance and prize in your fun competition. Giving me all the nice summer vibes for sure! =D