>>44096170If we go by milk drink's learnset, only miltank and gogoat, but I would imagine all female mammal-like mons can produce milk: raticate, wigglytuf(?), ninetales, raichu, sandslash, persian, slowbro, slowking, dugtrio, nidoqueen(?), primeape, arcanine, hpyno, rapidash, dewgong, eevee & evos, lapras(?), snorlax, mew(?), mewtwo(?), typhlosion, furret, ampharos, donphan, ambipom, granbull, girafarig, azumarill, crobat, ursaring, houndoom, piloswine, mamoswine, weavile, stantler, smeargle, entei, raikou, suicune, linoone, obstagoon, grumpig, plusle, minun, wailord, slaking, walrein, delcatty, spinda, camerupt, mightyiena, absol, manectric, zangoose, infernape, bibarel, pachirisu, luxray, skuntank, floatzel, hippowdon, lopunny, purugly, lucario, shaymin, emboar, samurott, zebstrika, simisage, simipour, simisear, watchog, stoutland, mienshao, emolga, audino(?), liepard, zoroark, beartic, excadrill, sawsbuck, cinccino, darmanitan, musharna, heatmor, bouffalant, swoobat, chesnaught, delphox, diggersby, dedenne, meowstic, pyroar, furfrou, pangoro, slurpuff, incineroar, primarina, gumshoos, lycanroc, silvally(?), togedemaru, mudsdale, komala, bewear, oranguru, passimian, rilaboom, cinderace, greedent, dubwool, boltund, morpeko, indeedee(?), copperajah, thievul, urshifu.
Even more if you include all the weird humanoids (alakazam, machoke/champ, hitmons, gardevoir, jynx, nuzleaf, shiftry, etc.) and the gender unknown legendaries (victini, swords of justice, xerneas, etc.).
