For the average observer, Pokémon battles as the extension of the Pokémon world are purely imaginative. Fervent fans may beg to differ and consider them almost realistic. Regarding that matter, though, Pokémon battles have been depicted in various ways in the games and media. As a result, it may be hard to determine what is real about them, including how they would actually work. This post involves taking considerations from these various depictions and conjecturing an accommodative perspective for the realism of Pokémon battles.
The classic depiction of Pokémon battles, as in the main series games, is a turn-based affair where two Trainers decide on Pokémon moves and everything is processed based on the logic and interactions of the moves. The turn-based approach works, especially given that the main storyline is based on battles with the AI, but realistically, it has some flaws. It is hard to expect two people to give move commands at the same time vocally yet in secret, given the expected layout of Pokémon battles; a person can always react once information by another is given. It is more sensical to think of the turn-based approach as a "shim" to advance the main storyline at one's own pace, or as a strategic mode of virtual play, but not as a real-world framework, at least without special technology.
Active depictions like in Pokémon Go or Pokkén Tournament could be considered to be more realistic, and the latter itself could be considered as a special case where the Pokémon are active for themselves with little human input. For Pokémon Go, there is still quite a bit of human input in deciding whether or not to attack with the Fast move, which Charged move to use, and when to switch. And so for the former, the problem of competitive secrecy arises again, one that could be resolved with certain technology that links Pokémon and their Trainers and sequesters participants, but is otherwise unrealistic for a common Pokémon battlefield setting, even exactly as depicted in Pokémon Go.
The depiction of battles in the anime seem to be quite realistic and even "hyperreal" in some cases, the latter concern of which has led to flak from actual competitive game players and maybe even the viewers themselves. Yet, it does satisfy the constraint of Pokémon battles being out in the open with little secrecy as is commonly depicted. Without the bits that some consider "hyperreal" - perhaps as a form of "artistic license" - the realism is quite possible, even down to the Pokémon themselves having their own intents that hopefully do not conflict with those of the Trainers. This would be alongside the realism offered by battles in the style of Pokkén Tournament.
While people, fans or observers included, may never know how Pokémon battles actually work out in its reality, at least a few things could be gleaned from all their various depictions to conceive a viewpoint that accommodates a realistic (or if it could actually be realistic) point of view. Regardless, Pokémon and its battles remain as something that in the fabric of the real world is something stitched out of a vision of dreams. But for those involved with them day in and day out, even with footnotes, they may just be as real as can be.
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