Windspeakers Blessing and Lux

A confusion I have about windspeakers blessing is on champions like lux and thresh for example. Lux's W hits an ally, and herself. Does her ally gain the resistance buff, and not lux? or do neither get the buff because lux's W is simultaneously a self cast? Thresh, wish his lantern shield buff as well opens a similar question.

Other questions arrive to me as well such as Locket of the iron solari, windspeaker give buffs to those with locket's shield up and not the shield caster? or does nobody receive the buff because locket's shield also grants the caster a shield?

Can anyone clear this up?