The fried oyster omelette is quite a common dish in asia actually and yes it is inspired by Taiwanese.
So when my family make it ourselves, we also use tapioca flour in the mixture, put the egg straight in there, add grated carrot & white radish, also sauted onion. We go with local oyster because it's small, therefore it's not as snotty as the european ones and faster to cook. The pancake is thick most of the time.
What we wanna get is that almost-mochi-like, chewy texture on the pancake and we can do the sauce as we please, whether we want it sweet & sour, sweet & spicy or anything else. It's totally up to us. We always put vegetables in the sauce too like carrots, broccoli, cauliflower, green beans, bell pepper, also pickled cucumber sometimes.