Is the above change in the glow of color of lantern supposed to happen? Or its wrong?
The one hanging on chain is blue and the one placed on wall is cyan(which suits nether themes more cuz its similar to soul lantern/torch).
Notes:- I have not tested it with other lanterns tho.
BetterEnd version:- 1.6.0

And jst wanted to know
Will these lanterns have a same function as soul lanterns/torches/fires like luring away piglins and hoglins?

It is intended, the color is based on the position of the lantern. As far as I know, there are no plans to add the piglin_repellents tag to the mod lanterns (but I could be wrong of course).