Motivic weightless complex and the relative Artin motive

We construct a motivic analogue of the weightless cohomology groups [18] and demonstrate several expected properties - ring structure, Kunneth, functoriality for certain morphisms etc. We also demonstrate the expected relationship with the motivic intersection complex of Wildeshaus [26], [25] (whenever it exists). The methods also give another construction of the weightless cohomology groups over any base field. In characteristic 0, this motive coincides with the motive EX of Ayoub-Zucker [3] and recovers the motivic construction of the reductive Borel-Serre compactification of Shimura varieties.