Ibiza height - EPSG:9394

WKT

VERTCS["Ibiza_height", 
	VDATUM["Ibiza"], 
	PARAMETER["Vertical_Shift", 0.0], 
	PARAMETER["Direction", 1.0], 
	UNIT["Meter", 1.0]]

WKT2

VERTCRS["Ibiza_height", 
	VDATUM["Ibiza"], 
	CS[vertical, 1], 
	AXIS["Gravity-related height (H)", up, 
		LENGTHUNIT["Meter", 1.0]], 
	ID["EPSG", "9394"]]

Data from @esri/proj-codes

{
  "wkid": 9394,
  "latestWkid": 9394,
  "macro": "PE_VCS_IBIZA_HT",
  "name": "Ibiza_height",
  "wkt": "VERTCS[\"Ibiza_height\",VDATUM[\"Ibiza\"],PARAMETER[\"Vertical_Shift\",0.0],PARAMETER[\"Direction\",1.0],UNIT[\"Meter\",1.0]]",
  "wkt2": "VERTCRS[\"Ibiza_height\",VDATUM[\"Ibiza\"],CS[vertical,1],AXIS[\"Gravity-related height (H)\",up,LENGTHUNIT[\"Meter\",1.0]],ID[\"EPSG\",\"9394\"]]",
  "description": "Ibiza height",
  "authority": "EPSG",
  "version": "9.8.13(12.9.0)",
  "deprecated": "no",
  "areaname": "Spain - Balearic Islands - Ibiza",
  "extent": {
    "slat": 38.77,
    "nlat": 39.17,
    "llon": 1.12,
    "rlon": 1.68
  }
}