Hi there!
You are right! Using Moving Aggregation you can simulate negative lag interval in Lag Column node. Window type is Forward, window length-1 determines the lag interval and aggregation is Last on lagging column.
Additionally there is another way using just a bit of filtering where number of excluded rows determines the lag interval 
Workflow is attached so check it out and if any questions feel free to ask.
2019_04_03_ReverseLagColumnOption.knwf (16.2 KB)
Regards,
Ivan