Arcpy Geometry class .ProjectAs function

does anyone have experience of using the .ProjectAs ArcGIS geometry class? I'm creating a point shapefile. The points are being read from a text file as WGS1984 lat/long (EPSG 4326) and I want to project into OSGB (EPSG: 27700) and then insert into blank point shapefile using InsertCursor. I can create the point geometry but when inserting the row is doesn't apply the projection to OSGB.

http://pro.arcgis.com/en/pro-app/arcpy/classes/geometry.htm

with open(nmealist,'r') as srcFile:
with arcpy.da.InsertCursor(OutShp, ["SHAPE@", "SHAPE@X", "SHAPE@Y", "SHAPE@Z"]) as InsCur:
    for fileLine in srcFile:
        # split the line up into a list
        lSplit = fileLine.split(",")
        if len(lSplit) == 1:
            lSplit = fileLine.split(",")
        if len(lSplit) > 1:
            # more than just one word on the line
            pointsOK = True
            try:
                FILENAME = str(lSplit[0])
                DOS = yymmdd
                TIME = str(lSplit[1])
                EASTING = float(lSplit[3])
                NORTHING = float(lSplit[2])
                HEIGHT = float(lSplit[4])
                HEADING = float(lSplit[5])
                IVA = float(lSplit[6])
                FLIGHTID = sortie

            except:
                arcpy.AddWarning("Unable to translate points")
                pointsOK = False

            if pointsOK:
                newGeom.SpatialReference = srwgs1984 # set spatial reference
                # create a point geometry from the 3 coordinates - EASTING, NORTHING, HEIGHT
                newGeom  = arcpy.PointGeometry(arcpy.Point(EASTING,NORTHING,HEIGHT))
                # project point into OSGB
                projectedpoint = newGeom.projectAs(srosgb)          
                InsCur.insertRow([projectedpoint, EASTING, NORTHING, HEIGHT])# insert this point into the feature class