public string Variable {get;}

//var voxelLayer = ... ;
//Must be on the QueuedTask.Run()

var sel_profile = voxelLayer.SelectedVariableProfile;

//Get the variable profile name
var profile_name = sel_profile.Variable;

//var voxelLayer = ... ;
//Must be on the QueuedTask.Run()

var profiles = voxelLayer.GetVariableProfiles();

//Select any profile as long as it is not the current selected variable
var not_selected = profiles.Where(p => p.Variable != sel_profile.Variable).ToList();
if (not_selected.Count() > 0)
{
    voxelLayer.SetSelectedVariableProfile(not_selected.First());
}