Ephedra works as a simple stimulant to wake up a drowsy brain, probably not good in the long term. Aim for good quality unground herb less than 8 months since harvest to reduce side effects.
Matcha is probably also a simple stimulant? One loaded with antioxidant and less overstimulating than ephedra or coffee. I dont have experience with that specific (unique) form of green tea but I've been browsing
Peng's cooking blog and her frequent use of matcha as a food dye looks fun
Gingko I tried. The gingko
extract pills seem to work. The foliage prepared as decoction, in proper dosage, produces a flavor that would never catch on as a variety of milkshake- thats for sure! Reminiscent of Peganum harmala, really.
Much of the ginseng on the market has most of its actives removed, beware of ginseng products that look like candies or beverages. The real deal usually states ginsenoside content. Sweet leaf Gynostemma tea may be a more reliable equivalent medicine (and much cheaper). The bitter leaf Gynostemma, if you happen to get it instead, is less ginseng like but corresponds to the traditional pharmacology on record for Gynostemma pentaphyllum (jiaogulan).
Glycyrrhiza... be careful with that in quantity. Its medicine, not food. Every year a few people die because they get candy made with genuine licorice and they eat it like its... candy. G. glabra is the dominant european form, G. uralensis is what the chinese use. G. lepidota grows wild in north america. The three are freely interchangeable in a medicinal context.
Centella asiatica - I hope it works, I've never tried it specifically for memory but its good for other things too and I'm trying to germinate seeds right now. Theres clinical evidence of larger doses (like when its used as a vegetable in sri lahnka) making neurons grow and branch like Lions Mane is reputed to do.
Withania somnifera (Ashwagandha) isnt on your list and probably should be. If you grow your own you can isolate the root bark. The actives seem to be mostly confined to the bark and the bark in isolation is twice as potent and chewable (the core is wood). It smells like a horse and I've never licked a horse but as an earthy hippie I like the flavor of the root bark