Those all could work on paper, but I'm not sure how the general consumer would handle it. Phones can get incredibly hot while charging, and that's without them being pushed hard. Not to mention the extra noise that comes from something like a Switch with passive cooling. It's for sure a solid idea on paper, but I'm not convinced something like this would work well.
Plus, imagine the blowback if a game targets console + "Expansion Pak" in handheld, with the consumer being left with a juttery low-res mess if they play it on their normal Switch 2. While the optics of a big budget game like GTA VI running poorly don't look good for Nintendo, I'd imagine having a bad experience unless you spend extra money and carry around more shit looks ten times worse. No, that wouldn't be too dissimilar to a game running bad on the base PS4 and running fine on a PS4 Pro, but I feel like the optics of it happening with the battery pack are worse, even if it would cost less for the consumer. A Hyper Ultra Switch 2 Advance/PS4 Pro is sold as a flat upgrade, and the PS4 Pro did things that the PS4 couldn't like output at 4k. The battery pack would just have portable games properly render at 1080p, or at least get closer to it. It wouldn't be an upgrade like a PS4 Pro; it would just be used to bring subpar ports/games "too big" for the system up to a slightly more playable state.
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