Change project unit node

Revit
2

I don’t think there is a node that will update units
Here is some python code that can

import clr

clr.AddReference("RevitServices")
from RevitServices.Persistence import DocumentManager
from RevitServices.Transactions import TransactionManager

clr.AddReference("RevitAPI")
from Autodesk.Revit.DB import *

doc = DocumentManager.Instance.CurrentDBDocument

units = doc.GetUnits()
length = SpecTypeId.Length
feet_fi = UnitTypeId.FeetFractionalInches

current = units.GetFormatOptions(length).GetUnitTypeId()

if current != feet_fi:
    units.SetFormatOptions(length, FormatOptions(feet_fi))

current = LabelUtils.GetLabelForUnit(current)

updated = LabelUtils.GetLabelForUnit(
    units.GetFormatOptions(length).GetUnitTypeId()
)

TransactionManager.Instance.EnsureInTransaction(doc)
doc.SetUnits(units)
TransactionManager.Instance.TransactionTaskDone()

OUT = current, updated