We weaned by first starting with one arm out. I did this for nighttime sleep as well as for the first nap because those were the sleeps she did best with. She would go down okay, but I often found that when she woke in the early morning (4 or 5AM), I would often have to reswaddle her to get her to go back down. I thought because we were weaning and she slept for most of the night without it, putting her back into it in the early morning was okay because we were on a gradual process. I would also do one arm for her first nap.
However, for her second nap and her catnap I kept a full swaddle. She just couldn't go down well for those naps without it.
We did this for about a 1-1.5 months, until DD was 4 mos old. I eventually moved all of her sleep times to 1-arm swaddle during this time. When DD was about 4 mos old, I removed the swaddle completely and put her into a sleep sack. There were times early on that she would wake during a nap and I would often have to take her arm and hold it down in order to help her get to sleep. The way I did this was to just cup my hand into a C-Shape and just place it over her wrist (so she couldn't grab my hand) like a handcuff. But, I wasn't holding her down - it was there so that when she jolted her hand wouldn't fly up completely. There was still enough room for it to move a little, but it would lift and hit my hand. Bit by bit, I have stopped doing this as well.
At first, it took much longer to get her to go to sleep and I totally expected that. It also took longer for her to settle if we had to do s/p. I was also concerned at first because she would grab her paci (we have sinced weaned her of that) or grab her face or her hair. After a while, I just figured out that she needed to rub her face/hair as part of her calming technique, so I let her do it.
Breaking the swaddle is a gradual process for sure and not every baby is ready at the same time. I would give it a try for a few days and if it's really not working, reswaddle and try again in a week or so. If you try for just one or two sleep times, I don't think that is enough. It will be hard at first, so I would go a few days before going back to the swaddle to give your LO a chance to get used to it.
Good Luck!