Will these work with DSA SP keycaps?
I believe it will work if your LED can shine through the caps.
It depends what you mean by "work". SP doesn't make any DSA caps that are truly backlit compatible where the legends are transparent and can glow. The only effect an LED could have is some general glowing through the whole cap, and an underglow. Have you already been able to see the effects that your LEDs provide on the SP DSA caps that you're referring to?
My experience is only with blank PBT DSA caps in white (WAN), mid grey (GDE), and black (NDY), and I've found that the white LEDs on my Shine 3 are only visible through the white keycaps. I would assume that with these color changers you would see the tinted color through the white caps, but probably a lot dimmer than without the cover. With all of the caps I have an underglow effect, and I would imagine this color would also be changed with these color changers, but again it will probably be a lot dimmer than without. It doesn't help that my keyboard has a black plate so the underglow isn't very obvious.
I bought my colour changers primarily for the recently announced Vortex backlit compatible PBT caps (OEM profile) for whenever they are released, but I'm also hoping they'll be able to provide a tint to my white DSA caps, and with the light grey alphas in Granite and Decked Out.
So in summary, you may be able to get a muted keycap glow and underglow with the colour changers, but it's only likely to work with lighter colored keycaps. Of course I can only speak about PBT and not ABS.
I hope that helps.