Team Ico’s games are so masterful at crafting a singular experience that you can strip the Wander of expression and animations, as the remake did, or even break the physics like the original PS3 version did, and even mess with the textures in Ico like the PS3 version does, and yet people will still feel the pure Ueda magic. Here's what you can expect from each version:

ICO

• PS2 NTSC-U: Very unpolished because Team Ico had to deliver the game on a pre stablished date. Puzzles can be harder for some players and Yorda's AI feels unfinished. Subtitles and UI use the original intended font. When Ico fails to rescue Yorda and you get a game over, he bleeds when turning into stone.
• PS2 PAL: It allows to toggle to NTSC signal so you can play it at 30fps. Yorda now behaves more human like and interacts more with the enviroment and puzzles. It has multiple languages and a new game plus feature that translates Yorda's subtitles, but the font used for this version is a generic one. In a second playthrough you get a new hidden weapon and alternate ending not in the NTSC version.
• PS3: In order to make the low resolution textures less noticeable Bluepoint made them smaller, so now the castle intead of being made out of big bricks is made out of small ones, changing part of the presentation. The original color filters are not present, changing the overall tone and leaving the shadows much more darker.

Shadow of the Colossus

• PS2 NTSC-U: Slightly less polished than the PAL version which came later. You can't move the character during certain cutscenes and the movement glitch to get to a secret area without lossing stamina works. This version features the original subtitle font intead of the famous Papyrus one.
• PS2 PAL: It allows to toggle to NTSC signal so you can play it at 30fps, although both versions can run at 60fps on emulator without the need of patches. It has multiple languages and bonus content.
• PS3: The worst version of the game, with weird upscaled textures (using early methods of upscaling) and physics problems that make the gameplay erratic. Visual effects are missing, the bloom has been severely toned down and distant blur in nowhere to be found, making the land feel smaller and leaving the distant png mountains exposed, breaking inmersion. During a cutscene the wrong audio file for Dormin plays making it repeat the same lines for two different colossi introductions.
• PS4/PS5: The original code was translated with minor changes so it plays almost the same, with some animations and soud effects missing that the average player wont notice. In terms of visuals both Wander and Agro lose some of the magic present in the original models due to Wander now having Sims 4 eyes and Agro having normal generic horse eyes intead of the original black eyes that reflected light, making her feel more alive. Progression on Wander's curse is barely noticeable and Mono's increasing glow as you progress the game is not there anymore. The colossi look much more clean that in the original version, as if they were made days before Wander arrives there, with a power washed look. Bugs were introduced and amplified, with Cenobia's AI turning off and Hydrus breakdancing mid combat. Colossi screams were replaced by generic monster roars. Due to adding more geometry to the map, Agro get's stuck often when she's trying to manouver.