In your astrological chart. The Alchemist lights up above all with Pluto, the planet that carries the most weight for this archetype in the whole system. Next come the eighth and twelfth houses, the two areas of the chart that speak of what isn't on display, and the presence of Lilith or Chiron. If your chart has water and fixed signs, the signal gets stronger: the ability to hold intensity without running away.
In your BaZi. The strongest signal is PianYin, the resource that feeds on the unconventional and learns by its own routes. It comes with the water element, the one of depth and introspection, and QiSha, associated with the pressure that forces transformation. Among the animals, the Dragon and the Snake appear.
In your Human Design. The heaviest signal is being a Reflector, the type that needs a full lunar cycle to know what it really feels. Right behind, tied, come Lunar Authority and Emotional Authority: the two ways of deciding that consist of waiting for the wave to pass instead of deciding at the peak. Line 3 of the profile, the one that learns by trying and getting it wrong, adds to it.
In your palmistry. Let's be precise here: hand reading does not calculate your archetype. What it does is fine-tune how it is expressed. In an Alchemist it usually adds information about the stages where that transformation was most intense and about how you live it in the body.
In your graphology. The same goes here: your signature doesn't decide that you're an Alchemist. It adds the nuance of how much of that intensity you show outwards and how much you keep, which in this archetype tends to be the difference between transforming and being overwhelmed.