Lost my hdmi 2.1 features cannot get them back.

The LG CX has eARC (HDMI port 2) so I would use this to the soundbar for audio. Connect the Xbox directly to the TV. That way you should get all the features working as normal.

some features will be lost if the sound bar does not have HDMI 2.1 ports.

Hello,

VRR is supported via HDMI 2.1. The Xbox One X is the only console that has HDMI 2.1. Xbox One S has HDMI 2.0. This Fall 2020 the new Xbox Series X will also support HDMI 2.1 features like VRR, Auto Low Latency Mode (ALLM) and up to 120fps support.

but if the video feed is not going though a HDMI 2.1 port, the signal / bandwidth to the TV is limited by the HDMI port the it uses, be it a straight connection or some sort a splitter,

4K 120hz requires a HDMI 2.1 port, no HDMI 2.1 ports, no 120hz at 4K

The LG CX has 4xHDMI 2.1 ports! The Xbox will be directly connected to it as I describe above.

eARC is not a signal splitter device. It is a feature of TVs the past few years that returns audio to an external device like a soundbar or amplifier.

Don't hold your breath on the EVE, they did something very similar a few years back on a laptop people wanted that never got released, and nobody got their $100 back.

Anyway, manufactures are in no rush to add HDMI 2.1 to their monitors. Until GPU's support 2.1, monitors will not. I been talking to a company called HDFury, they are widely use in the home theater world, I currently use their Linker for my projector. They
are in the works of making a HDMI 2.1 to Displayport converter. This will be an active converter, meaning it needs power and it also needs programming via a PC. They are just waiting on true 2.1 48Gbps chip sets.

I know that EVE has a poor reputation and i will never buy direct from them, I will wait until their monitor's are sold at or on major retailers site's such as Amazon before i buy.

The RTX 3000 series cards are out sometime in September or after and support HDMI 2.1 and with rumored DisplayPort 2.0

I'm not a fan of using HDMI to DisplayPort adapter / converters and will never use them, i prefer to connect straight HDMI to HDMI or DisplayPort to DisplayPort.

What features? The video feed is going straight into the TV. It is just the audio going to the soundbar from the TV.

4K at 120hz

If the sound bar uses HDMI 2.0, the TV will only be limited to 4K 60hz,

The video feed is not going into the soundbar. It is going into the TV. Hence all HDMI 2.1 features work as normal.

The TV returns the audio feed to the soundbar via eARC which does not require HDMI 2.1.