Of course lots of people have studied the rules in detail and these debates have been ongoing through the centuries and millenia, since the earliest times of Buddhism! But there is no chance of any international agreement to modify the Buddha’s words. Nobody today has the authority to do something like that. Therefore, most nuns find workable solutions in their own monastery and then get on with their meditation practise.
Every monastery is independent in their decision how they keep the vinaya. So you’d have to start on the local level. If you are involved in the group of monasteries associated with Ajahn Brahm, then talk to your local monastics. The Ajahn Brahm “lineage” is known to be a fairly strict vinaya tradition, so I’d be surprised if they were in favor of rewriting the vinaya. But I am not associated with them and really can’t speak for them at all.
I have presented my suggestion of how to make the vinaya gender-free in this thread (Genderless vinaya thought experiment).
As other people have mentioned already, most bhikkhunis are really just struggeling to survive and to keep their monastery running. Investing much time and effort in international vinaya reform is not a very high priority.