Yes it is possible to use Qty. from StopLoss feature and Place limit on maximum number of Quantities by using MaxOpenPosition feature.
Example: If you provide MaxOpenPosition as 100, it will reject new LE/SE signals if they can increase Net Position more than 100. It works for both Long and Short positions.
To enable this feature go to Application Settings > Symbol Settings > Tick MaxOpenPosition
You can refer to this article for better understanding: