I've sewn quite of number of hakama pants and found the patterns usually suggest they sit at your ankle. If you're 188cm and the pants are measuring at 190cm, you might have to heam them depending on the way they sit on your body.
I would suggest getting the longer size, only because too short hakama pants can look really funny (and noticeable). One of my first attempts were these
as you can see they are too short for me. Or with this cosplay
too long. I have since learnt my lesson. Here is a good example of proper length
or this one