I think it depends on how you injured your ankle. I strained the ligaments in my left ankle/foot and also have plantar fasciitis. This happened about a month ago when I was on holiday in Scotland. I was walking A LOT with the wrong shoes on and am now having problems doing anything that involves my foot.
I ice it down every night and wear a special ankle brace that helps alleviate the problem, plus take ibuprofen. I keep it elevated as much as possible. Very slowly, my angle is getting better.
I work at a Pilates studio and my trainer/boss has me doing exercises for my foot, but nothing that puts the weight of my body on it. Mostly I have something like a tube that I can put ice into, about the size of 2" pvc pipe, and I roll my foot over that and push on the whole arch of my foot. I also flex my foot forward and back.
I am able to use a rowing machine as long as I'm wearing my brace. It's a pretty good workout for the whole body, and I happen to own a rowing machine. I can do Pilates as long as I don't attempt anything that involves putting weight on my foot, like full planks or downward dog positions.
Hope you get better soon!