WRT making americanos more like filter I’m with the gently facetious comment above that you just make filter, but I guess you only have an espresso grinder and don’t want to make big adjustments. In that case, you can get all the complexity out of an espresso by going for lots of extraction, you can sacrifice most of the body you’re usually trying to preserve too. Choose a coffee which is recommended for filter brewing.
Reduce your dose, try going down by 3 or 4 grams. Grind significantly finer. Extract more volume, try 45ml. Aim for 30-35 seconds for the shot.
We just put a light roasted acidic Kenya on guest espresso, and to balance it we ended up at 95deg, 17g, 45ml yield, 35 secs. Tastes detailed and delicate when served with water.