So you wouldn't recommend something advertised to stimulate root growth... like a super bloom type fertilizer high in phosphorus? Or a probiotic type product advertised to stimulate the grow of mycorrhizae fungus (something like Rhizotonic Rooting Stimulator)? Or a product with Vitamin-B1 (like Superthrive or Hormex Vitamin B1 Rooting Hormone Concentrate) that are advertised to prevent "transplant shock"? Is "transplant shock" a thing or is it just fancy advertising speak for repotting at the wrong time of year? (Sort of like how the blueberry industry invented the concept of a "superfood" to sell a product high in antioxidants...) Are all these types of things snake oil when it comes to reviving weak, recently uprooted, plants? Just stick to regular fertilizer?
I've seen more recent studies that actually indicate that phosphorus can have a negative effect on roots that have been recently damaged (e.g. transplanting, root pruning).
Mycorrhizae and other soil biology gets hyped up a lot, and I think it really is essential in most modern horticultural and especially agricultural applications, but it's not that important in bonsai, and can even have a negative effect if mismanaged.
Vitamin B1 is a human nutrient, it has no effect on plants. I have no idea how this started as a myth and people believed it but looking it up tells me it originates from confusion with auxins, which will not be useful in a situation like this as they don't stimulate healthy growth in already developed root systems.
Transplant shock is definitely a thing and it just refers to the response a plant has to transplanting. In any specialist industry there's going to be words that mean very different or even just slightly different things than what they mean in regular English, like how a knight in chess is way different from a knight in medieval France. "Shock" in this sense just refers to the physiological reactions that occur within the plant, which are a result of hormonal processes and way too complicated to be worth getting into.
Yeah, they're all kind of snake oil. Botany/horticulture is a super huge field of study despite the fact that it's deeply entwined in all of our lives, so when you're dealing with a massive, uneducated audience the swindlers tend to hit it big. Professionals often use other brands and products from casual users. Sometimes they're not available to the regular person, unfortunately.
My recommendation is stick to regular fertiliser for giving your plants nutrients. All you need to grow a healthy plant is water, sunlight, and nutrients. In that order.