It would be nice to have this in-game but there's no way to do that without uploading the file to the server first and it's surprisingly difficult to emulate Graal exactly due to how it handles body palettes.
There's a confirmation in-game before you approve an upload for review correct? That may be a good time to let players check it out.
Oh damn that's a shame. The upload viewer linked above doesn't really do the trick and pasting your head onto a body or trying out how your head looks with a specific hat is pretty annoying because you have to manually allign everything correctly. Was hoping that this would be possible but I guess it's more complicated than that.
Yeah in the confirmation message you get sent when uploading something previews your upload but you can't check how it actually looks with other items unless you actually accept it after staff approval but that can take a long time and having to keep submitting the same thing with only minor tweaks just feels like I'm wasting the time of whoever keeps having to approve it.
What Heeble said below is another thing.
Our preview for uploads is useless compared to the staff preview. Especially when dealing with indexing issues.
The preview we get isn't 100% accurate. On your end your body for example could look perfectly fine while on the staff preview it'll show any indexing issues and (correct me if i'm wrong) also transparency issues. Unless you try find out who is online doing uploads and ask for what the problem is, you will never know and you'll be stuck in a loop of uploading your body only for it to get denied.
This all isn't really an issue and we've been living with it for years and years now but it would've just been much easier and convenient for players if it were possible to test our things ingame somehow. Thanks for your thoughts about it and for letting us know.