Thank you very much @NoRay for going above and beyond with Shipmodul. It's kind of close but still very NMEA0183 centric as Nick pointed out.   

Solving NMEA2000 transport over TCP/IP should be a simple binding issue with an open spec - which I guess is what OneNet does. You have to guess though since it is a walled garden proprietary spec.

Hence, a thousand flowers are blooming to solve this. I think the software that offers the most protocol compatibility is NMEAremote (an iOS app). Here's what it supports:

Actisense NGT-1 (IP)
Actisense W2K-1
Actisense W2K-1 (NMEA 0183)
AstraYacht
B&G - H5000
B&G - Triton Edge
B&G - Vulcan & ZEUST™
BarentsWatch AlS - Norway
Bonjour
comar i300W/i320W
comar NMEA-2-WiFi
Digital Yacht (TCP)
Digital Yacht (UDP)
Digital Yacht - NAVLink 2
DMK Box
DMK Box (NMEA 0183)
EKI-1351
Expedition
ezTCP CSW-H80
GMM (NMEA 0183)
GMM (NMEA 2000)
GoFreeT™
GoFree™ Tier 2
HelmSmart
iKommunicate
iMux (AdHoc)
iMux / eMux (DHCP)
JSON-Broker (TCP)
MQTT Client
Navinaut AIS (TCP)
Navinaut AIS 1.0 (UDP)
nke NMEA WiFi Interface
NMEA over IP
NMEAconnect Server
NMEAremote Server
Ocean Signal ATB1
ONWA KC-2W
PilotsTECH - AlS Pilot Plug WiFi
Pitufino
PredictWind DataHub (TCP)
PredictWind DataHub (UDP)
Quark-elec
RedBox
Sailmon
Sailor Hat WiFi Gateway (TCP)
Sailor Hat WiFi Gateway (UDP)
SailTimer Air Link
San Francisco Bay AIS
SeaMate Ch.1
SeaMate Ch.2
SeaSmart.NET (NMEA 0183)
SeaSmart.NET (NMEA 2000)
ShipModul MiniPlex-2Wi
ShipModul MiniPlex-3Wi(-N2K)
Signal K
Signal K (NMEA 0183)
Vela-Navega
Vesper Cortex
Vesper XB 8000 / Watch Mate Vision
vYacht
Yacht Devices
Yacht Devices - YDWG-02 (N2k)
Yakker