Do them both at once after clearing out some of the other giants. Looking at my demo, I took care of those plates when I was down to two giants.
The key principle is that monsters can't step on your sword, so you try to block giants and golems with it on the turns that they move, using half-turns to reposition when needed.
The process I used:
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×Lead a giant to the upper-right. I was facing left, standing on the plate at 2, with a rock pile to the southwest (though that was only important for keeping the other giant away). The plate southwest of that was clear, also important for dealing with the other giant while going through this process.
-Step south. Face NW. This will keep the giant in place.
-Face N, step north to break the giant.
-Go back south, turn sword, kill the golem that walks towards you.
-Step NW, step N to kill the northwest golem (you'll be safe because it's a half-turn).
-At this point I led the other giant south, so it wouldn't be able to step on me right away. Went back to the checkpoint below 2, turned NE, stepped NW on the half-turn, then N again to kill the golem on 1.
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