I have boxes of old slides which are in very poor condition. Mostly the problem is a red color cast on Anscochrome and some kodachrome slides. I use various color change sliders in Photoshop Elements 2019.
But here is the problem, if I use the Enhance, Auto color correction, then the photo comes out with either a green overall color cast or a blue overall color cast, there is nothing in between.
I get much the same result using Enhance, Adjust Color, Remove Color Cast, or if I use Enhance, AdjustColor, Adjust Hue/Saturation.
Is there any way to avoid a color cast of one color or another?
Have you tried File>Open in Camera Raw? Or try using a Levels adjustment layer.
Can you post a representative sample image so we can give you some better suggestions.
How are you digitizing these slides?
I completed scanning a bunch of old slides with a Kodak scanner. Some of the slides remained in good condition over the years, some had cracked and others had faded. Do a few at a time. As suggested by Greg_S, try camera raw, levels, and clone over defects. Where there is a large defect, try to select an adjacent "good" area, place it on its own layer, position it over the defect - ---- a digital patch.
Feel free to come back if you need help.
PS I don't use the auto commands. For this type of work I find it best to use adjustment layers, e.g. levels, brightness/contrast, hue/saturation, etc.