You can create the nodes yourself and set the IDs
I haven't gotten around to working around their serverless limitation here -- looking at their docs, the node ids have the prefix of the original document id, and you can delete by prefix
In any case, you can create nodes like this
from llama_index.core.schema import TextNode
node = TextNode(text=text, id_=id_)
Or you can edit existing nodes
from llama_index.core.node_parser import SentenceSplitter
splitter = SentenceSplitter()
nodes = splitter(documents)
for node in nodes:
node.id_ = "some_id"