I have no idea why but unreal was failing but it seems to be fixed using the following snipped in .plugin file.
{
"Name": "Hdr10PlusStandardEditor",
"Type": "Editor",
"LoadingPhase": "PreDefault",
"WhitelistPlatforms": [
"Win64"
],
"BlacklistPlatforms": [
"IOS",
"Linux",
"Android"
]
}