The same applies to collaborations such as the Final Fantasy XIV cooperation with Odin (which exists as far as I know) where I do not understand just how much of Square Enix is involved that for Sega to have the ability to update assets . When it was only just Phantasy Star-related things (like character outfits, cameos from other games, or alternative Sega-related properties) I could imagine this probably would have been achieved, or would be done. But in the Global version we already don't have the existence of Cougar NX therefore that I do not exactly know if there are other complications seeing Sega's properties which may also contribute not to updating everything they could within reason.
I can imagine that probably out there we will still see somebody wearing those older collaboration items even when they are not rigged up to the same standards as new cosmetics in a similar manner and that there definitely would have been outrage if it was made unusable or obsolete. Collabs that have had their cosmetics removed nevertheless have their assets exist on the sport so those will likely still be accessible for jp players.
Only improvements we will probably see is the new engine improving shadows, reflections, colors, particle effects and projecting them from the outfits. You can have a look how exactly implementing better shadows and colours can improve old equipment by assessing ReShade screenshots. Collabs that have had their makeup removed still have their resources exist on the sport so those will probably still be accessible for jp players. Only improvements we will probably see is the new engine enhancing shadows, reflections, colors, particle effects and casting them from the drapes. You may take a look how exactly implementing better shadows and colors can improve old equipment by assessing ReShade screenshots.
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