His other Pokémon like Charizard would be completely bewildered. Charizard might initially think that this Eevee is just some random Pokémon near its territory. But when it senses something familiar about the Eevee, it would be hesitant and curious. It could try to communicate in its own way, like using small bursts of fire to get the Eevee's (Ash's) attention. The Pokémon that Ash has a closer bond with would be more determined to figure out what's going on and how to help him.
His Pokémon would have a range of reactions. Some of the smaller and more timid Pokémon might be afraid of this new form of Ash. However, the ones that are more intelligent, like Bulbasaur, would start to analyze the situation. Bulbasaur might try to use its vines to interact with Ash - the Eevee, gently prodding and sniffing to figure out what's different. Overall, they would all be concerned and try to adapt to this strange new situation with their trainer.
At first, his Pokémon would be startled. They've always known Ash as a human. But then, they would start to adapt. Some Pokémon, like Squirtle, might try to play with Ash in his new form, thinking it's a new kind of game. However, his more loyal Pokémon, like Greninja, would be determined to find a way to turn Ash back. Greninja might use its special bond with Ash to try and communicate with him on a deeper level in this new form, to understand what happened and how to reverse it.
Some of his Pokémon might be very confused and sad. Pokémon like Pikachu, who has been with Ash for a long time, would probably miss the adventures and battles they had together. Pikachu might try to cheer Ash up and convince him to change his mind.
Some of his Pokémon like Pikachu might be very protective. Pikachu would stay close to Ash at all times, being extra vigilant in case any danger comes while Ash is in this new form. It would also be curious and might try to play with Ash's new fairy features, like his wings if he has any.
His other Pokémon like Bulbasaur and Charmander would also be startled. They might gather around Ash - Zoroark and sniff him out to make sure it's still him. They could be a bit hesitant to follow his commands at first because they're not used to his new form. However, as they see that Ash's spirit is still there, they would gradually start to trust and follow him again, and they would work together to figure out how to turn him back.
At first, his friends would be in disbelief. But then, they would start to adapt. Dawn might see it as an opportunity to study a Pokémon from a different perspective. Gary could be both amused and intrigued, and might offer some scientific theories on how it happened. Overall, they would all be concerned for Ash's well - being and work together to either help him get back to normal or help him thrive in his new form.
His friends would be very shocked at first. Misty might be a bit worried and try to find a way to turn him back quickly. Brock, on the other hand, would be more curious and start observing Ash - as - Pikachu to see how his behavior has changed. His Pokémon friends would also be confused. Pikachu himself might be both excited to have a 'Pikachu - like' friend but also a bit sad that his trainer is in this strange state.
His Pokémon might be really confused at first. They're used to Ash as a human, so seeing him as a Pikachu would be quite a shock. But some of them, like Pikachu himself, might feel a closer bond since Ash is now in a similar form.
His Pokémon would probably be very confused at first. Pikachu, for example, might try to zap Ash back to his senses if he starts acting like a Team Rocket member. They would likely sense that something is wrong with Ash and would do their best to get him away from Team Rocket's influence.
Some of his Pokémon might be confused. Pokémon like Pikachu, who has a very close bond with Ash, would initially be in shock. Pikachu would likely try to understand why Ash is doing what he's doing and might even try to stop him at first.
Some of his Pokémon might sense the change in Ash immediately. Pikachu, being his closest partner, could be both curious and a bit protective. It might stay closer to Ash during battles, as if it knows Ash has a new power to draw from. Other Pokémon like Charizard might be a bit more aloof at first, but as they see the benefits of Ash's aura powers in battles and in protecting them, they would come to accept and rely on it.