G.B.
As long as the person understands that time out is to help the child learn to get control of themselves, to remove them from a situation that is too stimulating, etc...and NOT for punishment then you don't have to have the child sit or stand any particular place.
Time out, as punishment, out isn't really something a toddler or pre-schooler has any concept of. They don't associate that they are in trouble or that they even did something wrong.
If you have a child that is misbehaving then you need to simply redirect them to do some other task and remove them from that particular situation.