ETRS 1989 NTM Zone 20 - EPSG:5120

WKT

PROJCS["ETRS_1989_NTM_Zone_20", 
	GEOGCS["GCS_ETRS_1989", 
		DATUM["D_ETRS_1989", 
			SPHEROID["GRS_1980", 6378137.0, 298.257222101]], 
		PRIMEM["Greenwich", 0.0], 
		UNIT["Degree", 0.0174532925199433]], 
	PROJECTION["Transverse_Mercator"], 
	PARAMETER["False_Easting", 100000.0], 
	PARAMETER["False_Northing", 1000000.0], 
	PARAMETER["Central_Meridian", 20.5], 
	PARAMETER["Scale_Factor", 1.0], 
	PARAMETER["Latitude_Of_Origin", 58.0], 
	UNIT["Meter", 1.0]]

WKT2

PROJCRS["ETRS_1989_NTM_Zone_20", 
	BASEGEOGCRS["GCS_ETRS_1989", 
		DATUM["D_ETRS_1989", 
			ELLIPSOID["GRS_1980", 6378137.0, 298.257222101]], 
		PRIMEM["Greenwich", 0.0], 
		CS[ellipsoidal, 2], 
		AXIS["Latitude (lat)", north, 
			ORDER[1]], 
		AXIS["Longitude (lon)", east, 
			ORDER[2]], 
		ANGLEUNIT["Degree", 0.0174532925199433]], 
	CONVERSION["Transverse_Mercator", 
		METHOD["Transverse_Mercator"], 
		PARAMETER["False_Easting", 100000.0], 
		PARAMETER["False_Northing", 1000000.0], 
		PARAMETER["Central_Meridian", 20.5], 
		PARAMETER["Scale_Factor", 1.0], 
		PARAMETER["Latitude_Of_Origin", 58.0]], 
	CS[Cartesian, 2], 
	AXIS["Northing (Y)", north, 
		ORDER[1]], 
	AXIS["Easting (X)", east, 
		ORDER[2]], 
	LENGTHUNIT["Meter", 1.0], 
	ID["EPSG", "5120"]]

Data from @esri/proj-codes

{
  "wkid": 5120,
  "latestWkid": 5120,
  "gcsWkid": 4258,
  "macro": "PE_PCS_ETRS_1989_NTM_20",
  "name": "ETRS_1989_NTM_Zone_20",
  "wkt": "PROJCS[\"ETRS_1989_NTM_Zone_20\",GEOGCS[\"GCS_ETRS_1989\",DATUM[\"D_ETRS_1989\",SPHEROID[\"GRS_1980\",6378137.0,298.257222101]],PRIMEM[\"Greenwich\",0.0],UNIT[\"Degree\",0.0174532925199433]],PROJECTION[\"Transverse_Mercator\"],PARAMETER[\"False_Easting\",100000.0],PARAMETER[\"False_Northing\",1000000.0],PARAMETER[\"Central_Meridian\",20.5],PARAMETER[\"Scale_Factor\",1.0],PARAMETER[\"Latitude_Of_Origin\",58.0],UNIT[\"Meter\",1.0]]",
  "wkt2": "PROJCRS[\"ETRS_1989_NTM_Zone_20\",BASEGEOGCRS[\"GCS_ETRS_1989\",DATUM[\"D_ETRS_1989\",ELLIPSOID[\"GRS_1980\",6378137.0,298.257222101]],PRIMEM[\"Greenwich\",0.0],CS[ellipsoidal,2],AXIS[\"Latitude (lat)\",north,ORDER[1]],AXIS[\"Longitude (lon)\",east,ORDER[2]],ANGLEUNIT[\"Degree\",0.0174532925199433]],CONVERSION[\"Transverse_Mercator\",METHOD[\"Transverse_Mercator\"],PARAMETER[\"False_Easting\",100000.0],PARAMETER[\"False_Northing\",1000000.0],PARAMETER[\"Central_Meridian\",20.5],PARAMETER[\"Scale_Factor\",1.0],PARAMETER[\"Latitude_Of_Origin\",58.0]],CS[Cartesian,2],AXIS[\"Northing (Y)\",north,ORDER[1]],AXIS[\"Easting (X)\",east,ORDER[2]],LENGTHUNIT[\"Meter\",1.0],ID[\"EPSG\",\"5120\"]]",
  "description": "ETRS 1989 NTM Zone 20",
  "authority": "EPSG",
  "version": "7.5.2(10.1.0)",
  "deprecated": "no",
  "areaname": "Norway - onshore - 20~E to 21~E",
  "extent": {
    "slat": 68.37,
    "nlat": 70.37,
    "llon": 20,
    "rlon": 21.01
  }
}