Hey guys need help in figuring out if 19x9.5+27 fit the front of my 2018 lexus is350 lowered on coilovers?

 

Without the tire size, hard to say absolutely for sure...but just based on the rim specs, I'd say it's an 80% no. At stock height there's bound to be some rubbing on turns and hard bumps.
Also depends how much you want to lower it, and if you're willing to camber in the front wheels for extra clearance.
It's likely a road you don't want to head down.

 

 

Depending on how much you drop it on the coils and the tire size, that will dictate if it rubs a little or a lot.
Anything can be made to fit, just depends on how much work, effort, and money you want to put into it.

If you had a 19X8.5 +30 with a 225/35/19, even if you dropped it 1.5 inches from stock height, you would probably be ok in most driving scenarios.
It might rub on big bumps or hard turns.

 

 

The rear wheels will be fine once you make an appropriate tire choice.
Here's my take on the fronts:
19x9 +30 should clear the brakes, and with the right tire size it shouldn't rub (likely a 235/35/19), but that depends on how low you drop the car.
19x9 +43 puts the rim way further in than you need (a +35 or +38 would be ideal). It may not clear the brakes depending on spoke design. However, an issue fix would be to add a 5mm spacer, essentially making it +38.
Worst case you can add a 10mm spacer making it a +33 offset.
It's too bad the offsets are at the extremes, something in the middle would have be perfect.

It sounds like you are looking at a 3-piece rim.