I have twins also, mine are 2 now and I also have 3 other children.
I had my twins in the room with me until 10 months old and they were very reliant on being rocked to sleep, we also had several night wakes still going on and I was honestly dreading transferring them to their own room in their big cots as I was sure I would never see my own bed again.
What worked for me was the following and it took about a week to achieve.
White noise: on the loudest setting positioned right in between their 2 cots, some people even use a Machine positioned near each cot. Consider a white noise machine for your toddlers room too, it helps so much with reducing the likelihood of one being woken by another crying.
Usual night time, wind down routine and put them down in the cot. The first night I sat between them and held each hand, and or patted them to soothe. We did have tears but I did not pick either of them up but I did comfort them with belly rubs or back pats. The first night took a long time for them to settle, and for each night wake up I came in and sat between them and patted them until they settled. It was a very long night and I spent most of that night camped in their room with a pillow and a blanket.
Night 2 I did the same thing except I moved to the opposite side of the room once I had patted and settled them. They settled much quicker than night 1. I did the same for night wake ups.
Night 3, same as previous except this time I left the room while they were still awake. When they cried I came back in for a few comforting tummy rubs or back pats but removed myself again once they were no longer crying. For night wakes, I did the same tummy/back pats but left the room as soon as the crying stopped.
For the rest of the nights I just repeated the above and gradually they learned that cot meant sleep, and that crying didn’t equal being picked up, but they did get comforted and I never left them to cry. By the end of the week we were down to just 1 wake up each through the night. By week 2 wake ups didn’t require me to do any settling, they started settling themselves back to sleep, after that they were sleeping through.
It was hard to stick to it, and so so hard not pick them up and give them a cuddle but it was absolutely worth it, they sleep great now go down between 6 and 6:30pm and sleep until 7am. In fact they sleep better than my 6 year old 🙈 who still wakes in the night!
There is a twin sleep support and advice group of Facebook that might be worth having a look at.