Nothing.
Both this site and V6performance.net have been dead for years now. Over on V6P, there are only 2 long time members who will respond to posts on occasion...myself and ScottWax (now a Moderator).
Most of this new generation of kids buying these old accords for beaters and cheap...
You can drive it like that with no issues. The 98-02 Accord ECU relies on the primary oxygen sensor to run the car. The secondary oxygen sensor is only used to monitor the airflow in the catalytic converter.
CARB only applies to Commiefornia.
Buy an aftermarket converter, the cost SHOULD be...
Not sure if the electric tape wrapped around the wires is factory. My guess is "Yes".
If you know how to wrap wires with electric tape, then remove that old tape and see if the wires in that area have been "sliced/cut/etc.
Loss of power sounds like the ECU is dipping into Limp mode. I am not sure why it would based on your symptoms. Always have your OBD-II scanned for any trouble codes (DTC), as a starting point.
Yes, they came with remote controls. I never used mine and didn't have any problems in 15 years.
You need to contact the person you purchased the car from and see if they may have installed a remote start or aftermarket alarm system. That antenna may be a receiver for the remote start/alarm...
I am just guessing here. You may have shorted out or tripped the SRS circuit and as a result, the ECU has shutdown and will not allow your car to start.
Only way to be sure is have a shop run an OBD-II diagnostic.