That would probably not help much here; you'd then end up caching pretty much the same stuff on node 0 and 1, so it would be like having two 32 GB nodes instead of one big 64 GB node. They would both be maximally fast, within the 32 GB memory constraint, but they would both have to swap if you wanted to exceed 32 GB of cached information.

Real sharding - storing totally different stuff on the two shards - would probably give a really good performance improvement. But real sharding is much more of a pain than just starting two copies of mysqld.