They still do Cherry profile keycaps. What's "OG" about GMK is that they still use Cherry profile.
But yes, they also do custom colors and legends, but the MOQ is higher and there is a cost associated with them (depends on whether they decide to charge this cost or take it upon themselves).
GMK does doubleshot ABS keycaps in Cherry profile -- sometimes when you have multiple colors (such as in the case of Originative Cyrillic or TA Royal Alpha), the additional color is pad-printed.
As for your question about Cherry keycaps, they can come either pad-printed, lasered, doubleshot, or dye-sublimated. It just depends on the board they come from.