Maybe for better handling?Why AWD? Plowing snow?
Don't need it for 4+ sec 0-60 on street tires.
A Tesla SDU won't likely fit in a CRX without reversing its position, to avoid hitting the firewall.Ditch it, put a Tesla SDU up front (in back will F up the balance of the car), batteries in the tunnel and rear seat area. Transmission takes up too much space & weight.
There is no tunnel in a CRX... unless for "battery" you're thinking of something like a single string of D-cells.
A CRX has no rear seat, exceptionally optionally in Japan where a bit of padding is optionally available for small children. Where the rear seat base would be is a small storage bin... that's good for about 1 kWh of battery.
But yes, a multi-speed transmission is unnecessary weight and bulk in a car which is too small for the conversion.