If the TV is built the same as the US model (it probably is - your model # is slightly different than ours as it is for the Australian Market), then according to the review linked in my previous post, “The TV has HDMI 2.1 bandwidth on HDMI ports 3 and 4, with both supporting up to 4k @ 144Hz. Unfortunately, HDMI 3 is the eARC port, so you lose one HDMI 2.1 port when you plug a soundbar into the TV.”
The TV only has HDMI inputs for the cable from your GPU. The TV has no DisplayPort (DP) inputs that you can plug into. You are going to run 3 cables from your GPU, one to each TV.
Since your GPU has only one HDMI output, you HAVE to use at least two of the DisplayPort 1.4a outputs. In other words:
- Cable #1 goes from GPU DP #1 output → to → TV #1 HDMI port #4 input
- Cable #2 goes from GPU DP #2 output → to → TV #2 HDMI port #4 input
and either:
- Cable #3 goes from GPU DP #3 output → to → TV #3 HDMI port #4input
or
- Cable #3 goes from GPU HDMI 2.1 output → to → TV #3 HDMI port #4input
Since you only are going to plug one cable from your GPU into each TV, for the best performance options (below), you’re going to plug it into the TVs port that allows has the most bandwidth, which is HDMI port #4 (HDMI2.1 (ALLM, VRR, 4K@144Hz)). That leaves the TVs port #3 free for a soundbar, if you want to add external speakers, and ports 1 & 2 free for any other HDMI-compatible device you might want to plug into the TV at some point in the future.
The TV supports a number of resolutions (listed in the review), but for MSFS the ones we are interested in are:
a) 4k @ 60Hz
b) 4k @ 60Hz @ 4:4:4
c) 4k @ 120Hz
d) 4k @ 120Hz @ 4:4:4
(The 4:4:4 option is useful for ClearType text display for PC productivity and gaming with fine text.)
Both the DP & HDMI outputs support 4k @ 60Hz. 4K @ 120Hz is supported with Display Stream Compression 1.2 (see this article), but I could not find out if the GPU support this. Perhaps others might know the answer to this.
HDMI 2.1 supports both 4k @ 60Hz & 4k @ 120Hz, so at least one of your TVs could run at 4k @ 120Hz if you chose:
Cable #3 from GPU HDMI 2.1 output → to → TV #3 HDMI 2.1 port #4 input.
There are various opinions as to whether running MSFS at 60 Hz or 120 Hz makes an appreciable difference. Higher rates provides smoother motion, but some say the human eye cannot detect the difference, while others disagree! 
So what does this mean for your cables?
Since, officially, the maximum length of a DisplayPort cable is up to 3m (9.8 feet), you should plan your TV layout such that the HDMI ports at the back of at least two of the TVs are no further than 3m from the GPU outputs at the back of the PC, following whatever path you want your cables to follow. If the 3rd TV is more than 3m away, then using the HDMI output - to - HMDI input option would address that problem.
With me still? 
Now, cables can be bi-directional or uni-directional. As the names suggest, signals in a bi-directional cable can travel in both directions, but only one way in uni-directional cables.
Since your signals travel from the GPU to the monitor, If you choose uni-directional cables, the signal traffic MUST be FROM Display Port TO HDMI.
So, you’ll need:
- For TV #1, a Display Port 1.4 or 1.4a 4K 32.4 Gbps to HDMI shielded cable.
Or a Display Port 2.0 or 2.1 4K 80.0 Gbps to HDMI shielded cable (overspec’d for your GPU, but will work)
- For TV #2, another cable, identical to that for TV#1
- For TV #3, another cable, identical to that for TV#1
or a HDMI 2.1 48.0 Gbps to HDMI shielded cable.
[Edited 01/19 to remove the words “input & output” for the cable descriptions above which, on re-reading, could be confusing]
OK, apologies for the super-long post, but there was lots to cover. PLEASE, can others review what I’ve written & point out any errors, especially if you have a 3-monitor 4K setup. I do not guarantee that what I understand is necessarily true, as I do not have 3 4K monitors myself, and so am not speaking from personal experience. Thanks! 
