I am going to assume that this is a posting alt and you have a lvl 50+
Pet charms are fairly easy to farm. Do all the Petbattle WQ’s on all of your available characters in both BfA and SL with lvl 1 pets (the battles scale to your highest pet lvl when they are WQ’s.)
Then, there is a petcharm vendor in Oribos that will sell you +25 stones for the new petcharms (introduced in BFA). He is in the same room as the mog vendor. Make sure to stuff them into an array of different pet types. Now go out into the world and farm up them new pets, while continuing to do the petcharm wq’s as they show up.