Python scripting error (merge)

I've been trying to use this code to add a field to, merge, and sort multiple feature classes:

import arcpy, os

arcpy.env.workspace = r'W:\S&P\s&p techs\Emily\TownshipsDissolved\FinalDissolved.gdb'

#Looping through dissolved feature classes, adding 'Name' field and writing
#feature class name in the added field.
fcs = arcpy.ListFeatureClasses()

for fc in fcs:
    arcpy.AddField_management(fc, "Name", "TEXT", field_length = 50)
    with arcpy.da.UpdateCursor(fc, "Name") as cursor:
      for row in cursor:
        row[0] = fc
        cursor.updateRow(row)


#Merging the multiple feature classes into one named OSRS_ORN_NER.
mergeOutput = r'W:\S&P\s&p techs\Emily\TownshipsDissolved\FinalDissolved.gdb\OSRS_ORN_NER'
sortOutput = r'W:\S&P\s&p techs\Emily\TownshipsDissolved\FinalDissolved.gdb\OSRS_ORN_NER_new'

arcpy.Merge_management(fcs, mergeOutput)


#Sorting by HWY_NUM_PR and replacing OSRS_ORN_NER by the sorted feature class.

arcpy.Sort_management(mergeOutput, sortOutput, [["HWY_NUM_PR", "ASCENDING"]])

but when I run it I get an error that says this:

does anyone know what I'm doing wrong??