Well, enemies are going to try to flank you. That's inevitable - I believe they're programmed to do so. If you have 3+ enemies attacking your tank it's almost inevitable that they'll flank you - which is realistic. Try fighting 3 guys at once, keeping them in front of you all the time - good luck with that.
You can try manipulating the battlefield in such a way, that enemies can only attack the front of the tank - like using Ice Wall for example.
But, even if your tank is flanked (but has one-two enemies in front of the shield) Shield Wall is still very beneficial, because it prevents all/almost all damage from enemies in front AND generates guard which mitigates some damage done by the flanking one.
If you lock on target, I believe your character will turn their shield towards them automatically (especially if you leave that character for AI to control).
Are you sure it is possible to "lock" target?
When you have a target in melee rang and you lock into it, then press the attack button (R on PC by default), the character turns into right direction and attacks that enemy. I believe Shield Wall works the same - I'd have to check but I suppose so, as I haven't had much problem with that as of yet.
Having to use TacCam to issue movement orders for companions is far more annoying.
I'm also unsure how to stop using Shield Wall. For some reason It seems I cannot break it, and my character stays in that stance until stamina runs out/battle is over. Anyone knows how to stop sustaining the ability?
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