Some Re:Zero fanfic ideas, crossover mostly

Some more Re:Zero X Pokemon ideas:

Idea 1: The Re:Zero world was once a world with relatively friendly Pokémon, but that changed with the Great Disaster, especially the introduction of Mabeasts (a subset of especially aggressive artificial Pokémon in this) greatly disrupted the ecosystem. This caused the remaining Pokémon to become more aggressive(new Regional Variants) and for the aggression of them and the Mabeasts to ruin the reputation of the non-aggressive ones, forcing them to become more aggressive in a feedback loop(destruction of old records during the great calamity didn't help much). The Poke Ball was never invented in this world. Subaru is from the regular Pokémon world, knows how to make Poke Balls by hand, has some Pokémon friends, and is on a mission to mend the gap that has formed between people and Pokemon over 400 years(last one after a while, could add making a gym challenge to this). Subaru's history pre-summoning is very malleable, could have him have some original history, overwrite any of the game protagonists' journeys, even overwrite Ash's journey, or any of the Pokémon fic ideas I posted including the one below or the summon all of Pasio one.

Could also make Spirits a subset of Pokémon here thanks to their elemental attributes and ability to evolve. Legendary Pokémon definitely exist, but would be quite a bit more elusive thanks to the strained relationship. Probably have the Dragons be legendary Pokémon and have it so the only well-known legendaries are dragons or great spirits, along with an extreme lack of dragon type regular Pokémon leading to the dragon type being synonymous with legendary. Could even have a couple Ultra Beasts that came in and got stranded, going after any Isekai character thanks to them being Fallers. Species-wide adaptations are more prevalent among ones that live shorter lives on average, longer-lived ones tend to be more aggressive thanks to experiences earlier in life and not genetic adaptations(unsure if it's easier to befriend animals that had a bad experience or ones predisposed to be aggressive). There could also be some small groups that are able to continue being friends with pokemon, but they all have to be viewed as freaks and/or formed and isolated since around the Great Disaster. A group that I thought can be given this role is the Sanctuary inhabitants. Comment about Earth Dragons being similar to Cyclizar and having Earth Dragons that be one of the few species to have an almost purely positive relationship with humans post-Great Disaster. Meli's abilities similar to N. Flugel planted a bunch of Apricorn and Berry trees, Flugel tree being an especially tall one (Apricots and berries are technically invasive species, but minimal damage to the environment, especially compared to Mabeasts).

Idea 2 (warning: spoilers to various Pokemon games): Subaru is a regular person from the Pokémon world, but he and his family happened to be unlucky enough to catch almost every important event throughout the series when visiting areas or vacationing. Like he happened to be in Silph Co. during the Team Rocket takeover then they decided to immediately take a vacation to Hoenn and be in Sootopolis during Groudon's/Kyogre's clash and Rayquaza stopping them(I guess in Primal Forms for the first 2) along with seeing the battle on top of Sky Pillar and the destruction of the meteorite by Mega Rayquaza from a distance(rest of the satellite footage could get leaked later). 3 years later, get caught in Goldenrod Radio Tower during the Team Rocket takeover then happen to be on Spear Pillar when Dialga and Palkia almost remade the universe then seeing Giratina stop that and seeing the Sinnoh Champion and some kid(whom shortly after becomes the Sinnoh champion) go into the portal. Sometime after this, they happen to encounter Team Plasma during BW. 2 years later, they visit Unova again and catch the Opelucid City freezing, deciding to divert their vacation to another region immediately, landing on the small Geosenge Town in Kalos, catching the Ultimate Weapon coming out of the ground and them being suck there thanks to Team Flare blocking the exits, with them witnessing the weapon destroy itself(could add an inability to dying of age to them and everyone else in that area because of it if you want). Later, they happen to be at the Alter when Cosmoem evolves and Necrozma absorbs them and sees the light get sucked away then leave, seeing some leftover Ultra Beasts after the insanity is over. A bit later, they happen to be in Galar during the Darkest Day 2 at a distance that allows them to see the entire final thing with Eternamaxed Eternatus, along with seeing Rose's announcement preceding this. Later, in Paldea, they can encounter the Titan Pokemon in the Asado Desert, running away and later finding out about the insanity that was happening in Area Zero when they were there from the final version of the Briar's Book, getting caught in the Pecharunt situation in Kitakami between these events. Could even add him being on Pasio for some of the insanity that happens there, or even the some of the other spin-off regions. Anyway, he definitely would have at least one pokemon friend ready to battle with all this insanity along with the Pokemon-typical stuff like Poke Balls and Rotom Phone after a certain point, could jury-rig Link Cable to communicate with parents sometime post-summoning. (Probably would have to headcannon the undefined waits to total take less than 4 years or so to make this work timeline-wise). Could even have this scenario cut off at some point and have him fill in for the role of protagonist in some game, was thinking Masters personally(or SV with the entire friend group being brought with him during a group hug or something). (Could age him to being 10-15 to be like the protagonists or not)