You all know the ones, Yasuo's W, Braum's W.
My problem with those kind of abillities is that they can be used too well by players as both an offensive and defensive tool, meaning while it is nice to have an abillity that can save you, but not when that abillity can actually make you or other teammates attack through it, I mean, a normal shield is supposed to block damage, maybe even knock back enemies, not have a freaking sword through it that you can attack with.
My point is, don't you think it's a bit OP for the player with the shield/ his team to attack through the shield?
As a Jhin player, I can tell you, I'm so glad when I see a Yasuo wall from which I can ult from, but I can tell that's a bit too op.
Edit: I see a lot of people misunderstood, I didn't mean all shields, such as Janna's, I meant physical shields that need to be placed down, like my examples of Yasuo and Braum.