The ST235/80-16" load E are a 80 psi tire.
The Load G Hartlands are a 110 psi rated tire.
The trailer wheels will need to have a 110 psi rating if you want to enjoy the full use of the G tires.
Running a commercial grade all steel ply carcass G 110 psi tire on a trailer at 80 psi isn't the best idea.
Hartland ST235/85-16 load G is another commercial grade tire made in china that first came out on commercial trailers in the '15 era. Like other made in china load G commercial class tire they are popular with owners of those type trailers. These tires have a 13/32" tread depth for a long miles of service life vs other ST tires with 8-9/32" of tread depth.
Check out other rv forums about Hartland commercial grade all steel ply carcass ST235/85-16 G tires. Hartland makes other size/C/D/E ST poly carcass tires so don't confuse them with the all steel ply commercial grade ST tire.