common problem on standard dipole stock antennas, O.R.T Micro Clover 5.8GHz 3 leaf antenna will be your best choice, with only weight 1 Gram, it would fit nicely on your whoop!! various colours available to choose for your custom whoop build!
Plug and Play with your vtx that use U.fl 3mm Connector Type!Or just cut the U.fl to solder directly to your vtx.

Specifications :

Frequency Range : 5500 ~ 6000 MHz
Gain : 1.4dbic
Axial ratio : .63
Polarization : Circular (RHCP)
SWR/S11 : < 1:1.5
Gain Pattern : Omnidirectional (360 coverage)
Connector Type: U.FL (3mm)
Cable: Flexible RG178
Length: 40mm (connector to top of lobe)
Weight : ~1 Gram