I’m looking for a pair of antennas for my box goggles which uses a diversity receiver.
   I have read two mushroom or omnidirectional at 90 degrees apart will give good range and allow you to fly around yourself.
  Then to use a bi directional and an omnidirectional if you plan on flying lower and through trees o behind buildings.
    
  Is there any reason why analog BNF drones are sold with RHCP antennas ?
  
  I was looking at Ethix Vas crosshair and Mushroom combo.
  There’s a TBS Vas crosshair and mushroom combo too but I like that Ethix has a longer stem on mushroom allowing it to be bent or reach about head .
   Any suggestions on a pair of antennas for CobraX box goggles with diversity antennas?

What kind of range are you looking for?

Omni's will only give you short range, even with 2.  Range with omnis alone will be less than 1 mile.  In my experience you start to have signal breakdown around a 1/2 mile.

If you want the widest beam width for long range use 2 directional ants.  If you want to fly behind yourself and still have long range forward, use both an omni and a directional.

RHCP is the most common.  LHCP performs equally to RHCP, even though there are myths out there that LHCP performs better than RHCP.  There is no comparison out there that supports this claim.  And electrically it makes no sense.

There are lots of comparison tests of antennas on YT.  If you have an antenna you like seek out those comparisons.  I can suggest antennas that I have been very successful with, but I haven't tried them all and perhaps you will find something you like more or it may even perform better.  TrueRC and VAS are 2 brand names that are always doing R&D on antennas so what was the best antenna 2 years ago may only be middle of the road now.  I have been out over 8 miles with a VAS Pepperbox and VAS Ion V2 (not made anymore) on EV800D goggles.  TrueRC and VAS cater to the LR crowd, and in my opinion are the best choices for LR.

I was looking at an omnidirectional and a patch.
There’s a TBS Fusion combo made by Vas and then Ethix makes the same antennas by VAS but sold separately and slightly different.
Here’s TBS Fusion.
https://www.team-blacksheep.com/products...asant_pack

Then Ethix https://www.team-blacksheep.com/products/product:4386
and Ethix patch
https://www.team-blacksheep.com/products/product:4387
I’ll keep looking but I think a omnidirectional and a patch will be a good start.