Future Vision and Link skills

Yes, it will allow L!Lucina, and the ally she is swapping with to get an additional 6 def/res. The reason why is because Future Vision is still considered a movement assist skill. Atk/Def Link is best for L!Lucina if you're using Future Vision as a way for her to go on the offensive, but if you're mainly using Future Vision as a way for her to escape when she is low on health, then Def/Res Link is better, because your swap target (the wall) will be able to tank more.