1st can be either to the genus cereus or pilosocereus. Something odd about it. Leaning towards cereus heavily.
2nd is Pilosocereus pachycladus
3rd is Stenocereus pruinosus
4th Is an euphorbia(a cactus counter part/analogue from africa and southern asia) , perhaps anoplia or some poligona/mammillaris hybrid
5 is an agave(cant help you with the type) maybe lophantha