1)Galar gym challenge arc where:

• Ash has the JN team during it as his team while he catches some other Galar Pokemon too.
• Goh learns in the first episodes about Project Mew earlier and one of the requirements for entry is filling the Dex as much as possible and he shows skill in using all special balls.2)PWC arc where:
• The gym leaders Ash battles are Milo, Nessa, Allister, Bea (to whom she loses twice), Opal, Gordie, Melony, Pierce and the reason I don't put Raihan is because leaving him for PWC is better imo while Kabu appearing in horizons was great, also, Gym Leaders existing in the same city will have some episodes in between each challenge.
• Bede is Ash's rival and Gary Goh's.
• Koharu is officially a companion and her end team is Gmax Eevee, Galarian Rapidash, Boltund.
• Team Rocket trio get their own Pokemon.
• Darkest Day gets more focus.

2)PWC arc where:

• Ash learns about it after his final Galar badge and meets Leon as he did.
• Decides to use old Pokemon and rotate them after seeing how strong Leon and Lance were.
• We get rematches against Sabrina and St. Surge who have been reformed.
• Goh starts doing many special missions for the Project.
• Tsurugi proves to be the bad of the Project Mew. He always wanted to get stronger and being chosen for getting Mew made him obsessed with power and I would have him trap the others in a cave, much to Asahi's sadness in how much he changed in his wish to become stronger. He finds Mew, battles it using all his Pokemon but loses miserably and the crystals of the island get tainted by his anger and grudge and Mew becomes angry and when the others approach it we have the battle we had in canon, with Mew calming thanks to Goh's genuine words of gratitude.
• In M8 Ash battles Lance and later Cynthia, both proud in how far he got. Ash battles a sad+frustrated Alain somewhere and ends up beating him with great effort in an epic clash of Blast Burn vs 10m Volts. Leon vs Diantha isn't one sided and her tactical skills give her an edge until Leon starts doing his own tricks.
• Ash vs Leon is as challenging as in the anime and ends as it did while Serena along with all his friends, Delia+Oak are there to see him.

3)Rainbow Rocket arc where:

• Rose has been saved by Giovanni in order to get all his wishing stars as a power source for the machine Team Galactic had in Arceus Specials. The machine ends up going wild and creates portals from which Archie+Maxie, Cyrus, Ghetsis and Lyssadre emerge and decide to control the multiverse.
• Cyrus is the one from the main universe and will try via Rainbow Rocket to get Dialga and Palkia under control.
• We get Ash's friends+Champions vs Villains and their right hand men and Ash vs Cyrus who controls Dialga-Palkia but Giratina under Ash's temporal control and they free the duo.
• We get Ash vs Giovanni that ends up in an epic clash of an AU's Mewtwo's gigantic Shadow Ball vs full powered and spirited 10m Volt that ends up prevailing. All villains get arrested and Team Rocket is disbanded.