ECML14 Grid - EPSG:10626

WKT

PROJCS["ECML14_Grid", 
	GEOGCS["ECML14-IRF", 
		DATUM["ECML14_Intermediate_Reference_Frame", 
			SPHEROID["GRS_1980", 6378137.0, 298.257222101]], 
		PRIMEM["Greenwich", 0.0], 
		UNIT["Degree", 0.0174532925199433]], 
	PROJECTION["Transverse_Mercator"], 
	PARAMETER["False_Easting", 108021.121], 
	PARAMETER["False_Northing", 263196.8721], 
	PARAMETER["Central_Meridian", -1.6], 
	PARAMETER["Scale_Factor", 1.0], 
	PARAMETER["Latitude_Of_Origin", 53.8], 
	UNIT["Meter", 1.0]]

WKT2

PROJCRS["ECML14_Grid", 
	BASEGEOGCRS["ECML14-IRF", 
		DATUM["ECML14_Intermediate_Reference_Frame", 
			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", 108021.121], 
		PARAMETER["False_Northing", 263196.8721], 
		PARAMETER["Central_Meridian", -1.6], 
		PARAMETER["Scale_Factor", 1.0], 
		PARAMETER["Latitude_Of_Origin", 53.8]], 
	CS[Cartesian, 2], 
	AXIS["Easting (X)", east, 
		ORDER[1]], 
	AXIS["Northing (Y)", north, 
		ORDER[2]], 
	LENGTHUNIT["Meter", 1.0], 
	ID["EPSG", "10626"]]

Data from @esri/proj-codes

{
  "wkid": 10626,
  "latestWkid": 10626,
  "gcsWkid": 10623,
  "macro": "PE_PCS_ECML14_GRID",
  "name": "ECML14_Grid",
  "wkt": "PROJCS[\"ECML14_Grid\",GEOGCS[\"ECML14-IRF\",DATUM[\"ECML14_Intermediate_Reference_Frame\",SPHEROID[\"GRS_1980\",6378137.0,298.257222101]],PRIMEM[\"Greenwich\",0.0],UNIT[\"Degree\",0.0174532925199433]],PROJECTION[\"Transverse_Mercator\"],PARAMETER[\"False_Easting\",108021.121],PARAMETER[\"False_Northing\",263196.8721],PARAMETER[\"Central_Meridian\",-1.6],PARAMETER[\"Scale_Factor\",1.0],PARAMETER[\"Latitude_Of_Origin\",53.8],UNIT[\"Meter\",1.0]]",
  "wkt2": "PROJCRS[\"ECML14_Grid\",BASEGEOGCRS[\"ECML14-IRF\",DATUM[\"ECML14_Intermediate_Reference_Frame\",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\",108021.121],PARAMETER[\"False_Northing\",263196.8721],PARAMETER[\"Central_Meridian\",-1.6],PARAMETER[\"Scale_Factor\",1.0],PARAMETER[\"Latitude_Of_Origin\",53.8]],CS[Cartesian,2],AXIS[\"Easting (X)\",east,ORDER[1]],AXIS[\"Northing (Y)\",north,ORDER[2]],LENGTHUNIT[\"Meter\",1.0],ID[\"EPSG\",\"10626\"]]",
  "description": "ECML14 Grid",
  "authority": "EPSG",
  "version": "11.009(13.4.0)",
  "deprecated": "no",
  "areaname": "UK - London to Edinburgh",
  "extent": {
    "slat": 51.45,
    "nlat": 56.1,
    "llon": -3.45,
    "rlon": 0.05
  }
}