Luma Noise for Lightroom mobile

I see that it works differently in Lightroom mobile, for example when I apply noise reduction this smoothes the image a lot in all areas of my image in general, on the other hand in raw power when I apply luma noise reduction this only reduces the noise in the parts of the image where there is luminance noise, but preserving the detail of the rest of the image

It's already there. Tap on detail and scroll down. The slider labeled "noise reduction" does luminance noise reduction and further down you'll find color noise reduction which does chroma noise reduction. In the desktop apps luminance is more clearly labeled as there is not enough space on the phone screen but they are the same thing.