Yes you can use non-HE fabric softeners in your "HE" high efficiency washing machine.
However you shouldn't use non HE detergent in your high efficiency washing machine because it would create too many suds which won't be washed out properly in the wash and rinse cycle.
Always use HE "high efficiency" detergent in the High Efficiency washing machine but you can use non "HE" fabric softener in the high efficiency washing machine.