>>54097961not trying to defend feebas or anything here, but the pokeblock minigame (first time I've heard it being called that btw) is super easy.. you just wait till post-game and before long the blend master npc will appear and help you produce gold blocks with minimal effort
assuming you have caught a modest feebas using synchronize, you can even use the resulting milotic to get master rank in the beauty contest, killing two birds with one stone
again, finding the fish is absurdly hard but evolving it not so much.. I actually rather enjoy the lore behind the method.. certainly preferrabe to grinding a magikarp clone to lv40 or something