I expect you have a 2 different licenses with 2 different banch od tokens, one for the first "Qlik Sense Site" (Server B, C, D configurad in sync pers.) and the other for the sencond "Qlik Sense Site" (Server A, in shared. pers.).
If this is the case, the only way they have to share applications is exporting/importing task,
You can do it manually or build up a batch (using API) to do that.