Pens/Inks: There are a few others but these are my go-tos and what I travel with. @kuretakejapan no 40 x2 (I keep one that is running out of ink slightly for dry brushing texture.) various pencils, gold and silver @sakuraofamerica pens for signing prints, @sakuraofamericamicrons for line work - I keep a brown set for red hair and skin tone outlines,@uniball_pen signo white pens,@pentelofamerica pocket brushes, carbon platinum ink for the Kuretake pens, and @finetec golds.
Watercolor and Gouache: primarily M.Graham brand. I've tried others and use one or two pigments from other brands - Daniel Smith and Qor in particular have some unique colors and high pigment content, but I like the feel, lightfastness, and pigment content of M.Graham. They bind their paints in the traditional way using honey, causing their paints to always appear tacky and slightly wet and requires little to no rewetting. I have close to every color but piece to piece I tend to only use 1/3-1/2 of the colors - sometimes less sometimes more. I also make individual limited palettes for larger projects.
Paper: arches watercolor sealed blocks hot press (pink blocks) 140lb 100% cotton. I use sizes 9x12, 12x16, 14x20, and 18x24, though I also use larger sheets for big work that is typically on the 300lb hot press paper and from time to time I use Fabriano hot press paper as well. Both are the best possible brands in my opinion and both give slightly different broad spectrum wash textures. I very rarely use the cold press or rougher texture paper because it's tough to do ink work on.