This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
崝 combines 山 (mountain) with 青 (blue/green), likely a phono-semantic compound where 青 contributes the sound and 山 suggests a mountain-related meaning. The exact historical development is uncertain.
A mountain 山 that is blue-green 青 like a distant peak. Imagine a steep, rugged mountain covered in lush green forests.
For ソウ, picture the soul (ソウ) of the mountain: the blue-green peak is where the mountain's spirit resides. Soul -> ソウ.