Whenever I do checks for these things in PSS gen 3 games, I am surprised by how well it works out on its own (admittedly it's more noticeable on Firered). For example, let's look at Elite Four Sidney's Pokemon. He has a Mightyena, whose moves include crunch and double-edge. From the looks of it, that's a physical attacker- but you may forget that in gen 3, ALL dark moves were special. Mightyena has 90 attack to 60 special attack. With the PSS, it makes better use of crunch, an overall buff. Cacturne has both 115 attack and 115 special attack, so I would call this one pretty lucky. Its moves include needle arm and faint attack, both of which are physical. In gen 3, both of them were special. So an overall net zero. He has a Crawdaunt that knows Surf but also Swords Dance. With or without the PSS, that doesn't synergize well.
In terms of game balance, I would say the addition of the PSS is about equal overall, with small improvements to some pokemon that lacked a strong stab move that worked with their attack stats (dark types, ghost types - all ghost moves were physical. Now think of Gengar with a physical Shadow Ball back then). One can look at Dragon Dance, which boosted attack and speed, but all dragon moves were special in gen 3.
The gym leaders, elite four, and trainers are full of Pokemon that have stat boosting moves and no STAB to go with it, but that was a limitation of gen 3 unrelated to any PSS patch. If this is what you mean, buffing those moves, then yes you can go into the game files and change Crawdaunt's Surf to Waterfall, among other things, but that would make it "stronger"- if you're that much of a balance purist. I assume not, since the balance in this game and perhaps all Pokemon games were such that a literal 10 year old could beat it. Personally I change those kinds of moves in my own games and buff and nerf moves slightly based off of Gens IV to VI (Outrage, Thrash, and Petal Dance only have 90 attack power in gen 3 but 120 by gen 6. Fury cutter has like 10 power in gen 3, but 40 in gen 6. These are the kinds of changes I agree with.)
But like I said, Firered benefits much better from it. Agatha has tons of ghost pokemon with high special attack and PHYSICAL shadow ball. You can get a Hitmonchan that learns ice punch, thunderpunch, and firepunch, (all previously special moves that became physical) etc.
My final point is that for anyone who has doubts about the PSS split in gen 3: it's an overall improvement.
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BUT, I have a separate issue. The RTC doesn't work on 3DS injection (hardware), and I'm wondering if anyone has the solution to that. If it's noon where I am it's around midnight in the game. Quite annoying.
![Pokémon CosmicEmerald Version [Updated! 12/24/2019]](https://data.pokecommunity.com/attachments/12/12241-e60210464949c0674584e600e9882479.jpg)
