In Flink, is there a way to merge two streams in stateful manner

[Muazim Wani]

Hi Team,
I have a use case where I have two streams and want to join them in
stateful manner .
E.g data of stream 1 should be emitted before stream2.
I tried to store the data in ListState in KeyedProcessFunction but I am not
able to access state  outside proccessElement().
Is there any way I could achieve this?
Thanks and regards