It's already on the latest FW so shouldn't be any issues there, I've just read a few things about arc not working too well.
Why would a soundbar have issues with ARC? Especially a modern one. Why not test it and if it has issues then look into it rather than trying to see if it will have issues or not as nobody can answer that as it should work on any TV.
ARC is well known to be problematic (that’s why eARC is coming) and I’d seen a few posts elsewhere with people having issues on LG TV’s. Of course I’ll be able to test it first hand, was just seeing if there was anything I should know about when setting it up.
I've never had any issues with arc on either of my setups on any tv.
I have an LG using ARC downstairs with an AVR.
I have had a Panasonic and a Sony upstairs using ARC with a Yamaha soundbar.