@yorman_steven_ladino How were you wanting to visualize this difference?
If possible, I would recommend using a single shift document with a start and stop timestamp, so you could first create the document with the start timestamp when a shift starts, and then update that document later to add a stop timestamp.
POST shifts/_doc/<shift_id>
{
"start": "2020-03-23T03:04:15"
}
POST shifts/_update/<shift_id>
{
"stop": "2020-03-23T09:00:00"
}
This is similar to what is described here: How to calculate the timestamp difference between two actions?
Then you could create a scripted field based on the difference between timestamps. There are some examples of doing date math in painless in this blog post if you want to learn more.