Hi Valter,
Are you looking at node dashboard in target node OR application dashboard, we confirm the source application from whcih node is moved will not have the node level data as we moved it but this should not affect tier and app level data already stored at old application , see if that clarifies.
feature related doc link for reference: https://docs.appdynamics.com/display/PRO39/Move+an+App+Agent+for+Java+Node+to+a+New+Application+or+Tier