
i followed 4,939 people on twit and i have NOT learned my lesson
i make games, theatre, AND A LOT OF NOISE

A bit jank as it's old and there's no real-time preview as opposed to Photoshop, but maybe something like Wally or some other Quake/Half-Life texture editing tool, as those made with limited palettes in mind?

Sir, I colorized photos I pulled off of a toy camera from 1998 using an image editor from 2005 on a refurbished desktop from 2009, and you are cautioning me that a program that you are recommending is old and jank. Your warning has arrived too late.
This looks better than most, but I kind of can't abide the default Windows color picker.
Checked a couple of other texture tools, including modern versions of both Wally and Slade, and literally every single one that I found uses the default Windows picker so no luck with those
Color editing in Aseprite is locked behind "edit color" button, in the latest version that's on Steam at least

there's an android app that might let you swap palettes easier (i'm on ios)--but it's one of those good old "sideload apk is hidden behind a discord link" type deals. i could reupload it if that works w/ your workflow, lmk--but honestly a lot of people do just use photoshop iirc
Back in my day we edited palettes using NOTEPAD and HEX EDITORS
(No seriously I just use Paint Shop Pro 7 for this. Palette editing is the main reason I've kept it around.)
Oh god I am flashing back to copypasting data into PVR files.
I've never used it. I'll have to give it a shot.
On PSP 7 I could save the palette file as a text file, edit the values, load it up. It worked surprisingly well.
The last time I had to edit an images palette, which was some time ago, I used the '02 or '03 version of Paint Shop Pro -- specifically because I remember it handling that better than (then current version of) Photoshop.
There are probably better options, but in a pinch PSP should work.
The Game Boy Camera Gallery is an awesome tool that, among other things, lets you manage palettes and frames for GB Camera photos, it letting you upload a save state file is also super convenient for a lot of workflows. https://herrzatacke.github.io/gb-printer-web/#/home
I regret giving away my GB and its camera so much. stupid me. Oh well.