while studies have shown introduction of foreign plants into local habitat often resulted in wiping out part or whole local species. eg are mimosa pudica from Brazil, eucalyptus from Australia. These are hardy plants that adapt very well in many various cond.
Since neps are often found in heath forest, there are factors limiting their adaptation - Local weather pattern, soil conds, seeds viability and their flowering pattern. an eg Introducing northiana into swamp area will resulted into their demise.
Period of flowering pattern often ensure certain species to breed among themselves. while hybrid among neps are common there are often pockets within certain area that they are not found among the population.
success of hybrid again doesn't ensure their survival, being limited by their viability and seeds count. Female flowers or male pollens may be sterile. some neps have high seeds count per pod but attained low germination and vice versa.
Therefore, introducing a foreign neps or local neps into another local area will be limited by the factors mentioned. My
2¢s