No, it's exactly what you suggested. Let's say you can get a microbial solution manufactured in a lab. You still have to distribute it and let it "grow" into the soil. That is exactly the opposite of what you said you wanted though. It's not the instant application process that fertilizers have. Therefore you actually do need to supplement the soil wholesale for an instant result. Waiting for the "dumb bacteria" to do their job costs money so it won't happen.