Question
Anything wrong with connecting L298Ns in parallel?
Answer
Nothing wrong. Hobbyist do it. Engineers can also do it. It also depends on cost/benefit/risk hobbyist/engineer trade offs.
Let me explain, starting with ULN2803, then L298N.
Part A - ULN2803A Case
ULN2803A Darlington Transistor Arrays - TI
3 Description
The ULN2803A device is a 50 V, 500 mA Darlington transistor array. The device consists of eight NPN Darlington pairs that feature high-voltage outputs with common-cathode clamp diodes for switching inductive loads. The collector-current rating of each Darlington pair is 500 mA.
The Darlington pairs may be connected in parallel for higher current capability.
Part B - L298N Case
By the same ULN2803 token, L298N can also parallel output for bigger current. Since the BJTs in parallel are from the same die, so they should self balancing out their currents.
Part 3 - L298N Dual Full Bride DC Motor Driver Module Case