This is possible, but only through manipulating the CIM, which is a bit tedious.
Python CIM access—ArcGIS Pro | Documentation
def highlightField(map, layer_name, highlight_field_name):
lyr = map.listLayers(layer_name)[0]
# Get the layer's CIM definition
cim_lyr = lyr.getDefinition("V3")
# Ensure the featureTable has fieldDescriptions to modify
# https://pro.arcgis.com/en/pro-app/latest/arcpy/mapping/python-cim-access.htm#GUID-C80C9CF4-67C8-418E-BEB5-386B18EE6097
if len(cim_lyr.featureTable.fieldDescriptions) == 0:
# No CIM field descriptions class; create one.
fDesc = arcpy.cim.CreateCIMObjectFromClassName('CIMFieldDescription', 'V3')
# Get field info and populate the new field description.
highlight_field_props = [f for f in arcpy.ListFields(lyr) if f.name == highlight_field_name][0]
fDesc.alias = highlight_field_props.aliasName
fDesc.fieldName = highlight_field_props.baseName
fDesc.highlight = True
fDesc.visible = True
fDesc.searchMode = "Exact"
# Add new field description to the CIM.
cim_lyr.featureTable.fieldDescriptions.append(fDesc)
else:
# Make changes to field description in CIM.
for f in cim_lyr.featureTable.fieldDescriptions:
if f.fieldName == highlight_field_name:
f.highlight = True
# Push the CIM changes back to the layer object
lyr.setDefinition(cim_lyr)
aprx = arcpy.mp.ArcGISProject("current")
highlightField(aprx.activeMap, "MY_LAYER_NAME", "MY_FIELD_NAME")
In my testing, the fieldDescriptions was indeed empty (as the documentation notes) so I created a CIMFieldDescription only for the field being highlighted. This has the effect of moving the highlighted field to the beginning of the attribute table view. If that is not acceptable, you will have to create a CIMFieldDescription for each field in the order you want.
