I'm biased as hell hahaha when it comes to the subject. The Adventures manga all the way for each and every generation. Below is just a short explanation as to why I prefer the Pokemon Adventure manga's take on the generations over the anime's.
Gen 1 - RGB is for many their first experience with Pokemon Adventures and I think what I love most about this is that Red is basically Ash but the writer ain't holding back. As for the Yellow arc, in my opinion Yellow is just one of the best female lead main characters I've seen of the Pokemon series.
Gen 2 - Okay, so honestly I can understand if someone chooses the Gen 1 anime over the Gen 1 manga but in the case of Gen 2, I honestly have a hard time seeing anyone choose the Gen 2 anime over the Gen 2 manga even if you haven't read the manga because as many of you know, Gen 2 is infamous for its filler in the anime whereas it's well-known for producing one of the best story arcs in the Pokemon series, the GSC chapter of Pokemon Adventures.
Gen 3 - For Pokemon Adventures, it has the best love story in all of the Pokemon series, some of the best Kanto fanservice in all of the Pokemon series, the best battle-focused story in all of the Pokemon series and perhaps the greatest fanservice I've ever seen in a Pokemon series, I'm talking Avengers-level of fanservice done right. Also I prefer the manga's take on Groudon & Kyogre, the Sevii Isles and the Battle Frontier over the anime's take that I think it's not hard for any anime fan to understand why because it's not that big of a bar to top since the anime greatly downsized or heavily altered the story and lore of the games.
Gen 4 - So if I had to recommend an anime fan what Pokemon Adventures arc to read, the DPPt arc would be it. This is because the arc reminds me why I love the days of Ash, Brock and Misty during the Indigo League. Dia, Pearl and Platina's friendship is easily the best friendship I've ever seen in any Pokemon medium that your actually reminded that these kids are actually freaking kids, not XYZ Ash who looks like a 16-year old teenager. You are reminded that these are literally just 11-year old kids being 11-year old kids, not caring much what the future has in store for them, that they just want to have fun and genuinely show fear and concern when thrown into a villainous plot like... well... kids! Also, Cyrus. Cyrus of the manga is easily the most intimidating version of Cyrus and I think what's surprising is I don't see people talk about this one important detail the manga nails about the games that the anime completely misses and that is Cyrus isn't some behind-the-scenes villain like Giovanni. He's a more personal villain who actually approaches the player various times and seeing such an important detail adapt into the manga, they absolutely nailed how intimidating Cyrus is as a villain who has a relationship with the main characters whereas in the anime, Cyrus doesn't really interact with Ash at all.
Gen 5 - It's Best Wishes, do I need to actually explain why the Pokemon Adventures BW and BW2 arcs are better than this?
Gen 6 - So I like the XYZ anime a lot but I still prefer Pokemon Adventures XY over the anime because much of the writing for the characters are so well-done in my opinion that it's one of those stories you can actually learn something. The main character whose based on Calem, X or Xavier, is this depressed recluse who stays in his room all day to the point that his introverted behavior has hurt his relationship with his friends and Pokemon who he knew since childhood. Then one day Team Flare shows up and wrecks the place. It is here that we see a main character who is not willingly entering the world of Pokemon but is forced to. He is selfish at times, he has trust issues and we can clearly see that he still wants go back to his quiet peaceful yet depressing and self-destructive comfort zone. In the end, it is not X who saves himself from his own reclusive behavior but instead by the friends and Pokemon who love him. And that ladies and gentleman, is why I prefer the Adventures take of XYZ over the anime's.
Gen 7 - So Pokemon Adventures SM definitely has some flaws here and there that honestly I understand why some may prefer the anime over this but I nevertheless prefer it over the anime because I just love how it dives deep into the jam-packed mysteries of Alola from the Tapu Guardians to the mystery of Cosmog to Lillie's and Gladion's relationship to the Aether Foundation to the strange appearances of the Ultra Beasts to the disappearance of Mohn to the mystery of Necrozma and more, all of these mysteries and we already see a number of players who are already involved long before the main characters start investigating that you start to wonder where this trail of cards down the rabbit hole is taking you, who is responsible for all of this, what are everyone's motives and just when the manga answers one of the mysteries, it leads you on to another mystery, another "Why?" If the SM anime is like the Yokai Watch of Pokemon, then Adventures SM is like the Gravity Falls of Pokemon and I just can't resist a good old fashion mystery involving Pokemon, can you?
