Error: The parser did not identify the text as a valid SQL statement due to STRING_SPLIT function not supported. (4380512)

Statement sample as follows:

SELECT

    p.BusinessEntityID,

    p.FirstName,

    p.LastName,

    v.value AS NamePart

FROM

    Person.Person p

CROSS APPLY

    STRING_SPLIT(p.FirstName + ',' + p.LastName, ',') AS v

Error: The parser did not identify the text as a valid SQL statement due to STRING_SPLIT function not supported.
The same SQL statement runs successfully in SSMS, but fails when executed in SQL Optimizer for SQL Server.

WORKAROUND
None.

STATUS
This issue has been logged as defect Id. SOFSS-1865 to be fixed in a future release of SQL Optimizer