After apply SO08958 on top of R14 SP2 as suggested by the Supportability Matrix, NRI inventory files (.xiu) are still showing Windows Server 2019 systems as "Windows Server 2016 Standard x64".
C002101[$40GeneralInventory$|$Operating System$|$Installation$]
C00010500Version|10.0
C00020201Major Version|10
C00030201Minor Version|0
C00040500Service Pack|
C00050201Build Number|17763
C00060500Name|Windows Server 2016 Standard x64
C00070500Vendor|Microsoft Corporation
C00080500Product ID|xxxxx-xxxxx-xxxxx-xxxxx
C00090500Product Key|**********-****-*****
C000A0500ReleaseId|1809
C000B0500InstallationType|Server
C000C0500ProductName|Windows Server 2019 Standard
C000D0500Licensee|Windows User
C000E0500System Path|C:\windows
C000F033CInstall Date|0|1579515327
C00100500Language|English (United States)
C00110101Hyper-v Capable|1
C00120101Hyper-v Enabled|0
Client Automation 14 SP2