Converting male looks into Alt Futa looks is something I'm looking to learn, I would love to hear about your process and how you use this plugin for that purpose.
Glad to know there's more people interested in doing this! Please note the proccess described below is only for male appearances that have their OWN textures, no default Skin Select male textures will work, since you won't be able to access them. (DM me if you have queries/frustration about this). I'll try to make a tutorial with pictures, but so far...
First, grab all the male hairs you like, go inside their addon, and drag the folders with the name of the creator of that hair into your Custom/Hair/Female directory. Appearance Loader will find them when it works its magic. Note that some Kemenate pubic hairs don't look good or break on an Alt Futa figure, so look for female pubic hair as a substitute.
Second, check in Package Manager (the white cube-shaped button) that whatever morphs the guys you want to convert have, are marked in “User Prefs” (to the right of Package Manager) as “Preload Morphs”, so they will always be available. Thiss is for looks on which Face or Body shapes are merged into a single morph.
Third, open the scene where the boy you want to convert to Alt Futa is, tweak him, make him look stunning, and create an Appearance Preset with him. If there is only that guy in the scene, you can continue there, creating a girl next to him. If not, create a new scene with a boy and a girl, side by side, with the same pose (default, or standing), and in their birthday suit

. You want the girl to have a Female Base UV (Skin Select tab). Light the scene well (3 lights are usually enough), so that their backs and buttocks are well lit too. You can add a floor and a wall in the background if you want. In the Female Morphs tab of the girl, check “Use Male Morphs on Female” (top right).
Fourth: select your boy, and load the Appearance Preset you saved. He'll help you compare your new Alt-Futa girl later. Now select your girl, and add these plugins to her: Alternative Futa, Appearance Loader, UV Swapper, Collider Editor (to retouch/ move down the testicles colliders as needed, although this is more advanced). In Appearance Loader, at the bottom, tick Change Morphs, Scale, Physics (if you want), Eyes, Mouth, Hair. DON'T tick Change Textures, or your girl will become a boy, not an Alt-Futa!
Now, still in Appearance Loader, at the top, click Load Vap Appearance Preset, and find the male appearance you saved. Voila! Your girl should have your boy's hair and shape, but with different body textures. If it still has a girl shape (sometimes happens), go to the girl's Male Morphs tab, search for MVR_G2Female, and set its value to -1.
Fifth, a tedious and tiresome part, but worth it! In the UV-Swapper plugin of the girl, load all the textures of your guy in the corresponding button: diffuse, specular, normal for face, torso, limbs… that's why you need a male appearance with its own textures. You can ignore the “set Genitals”, we will do that with Photoshop or Photopea. Well, this plugin will take care of changing your guy's textures to Base Female's UV, and save them in Saves/PluginData/mrmr32/UVSwapper. Go to that directory, select all those textures, cut, and paste into a new folder inside Custom/Atom/Person/Textures/FemaleBase. Rename that folder as you wish (“My_Boy_Alt_Futa” for example), and rename each texture also as you consider better (My_Boy_Face_D, My_Boy_Face_S…) Also add to that folder the male genitalia textures (difuse, specular, normal,...) of your boy, to use them later in the Alt Futa Plugin of the girl.
Sixth, veeery tedious, but much needed: I then load in Photoshop or Photopea all the torso textures (diffuse, specular, normal) that I have saved in the folder of my new Alt-Futa figure, and I put over it a layer with the Genitals texture (the one with a pussy on the navel) of some female figure or another Alt-Futa figure (MvFF has some good ones), I make a mask selection of the anus area and the inner part of the buttocks (will share the blueprint eventually), and I erase everything else of that texture. I adjust the tone, saturation and luminosity of that “Genitals” until it blends smoothly with the layer where I have the torso texture of my new Alt-Futa. If necessary, I retouch with the “stamp” tool so that there are no uneven areas, and I export the retouched textures to the texture folder of my new Alt-Futa.
Seventh, I then select my girl Alt-Futa, load the textures from the folder I created for my Alt-Futa girl, placing the textures I retouched in Photoshop or Photopea under Torso and Gens, that is, with a proper anus, not blank. Then I go to the Alt-Futa Plugin, and in the "Penis Material Options" section, I load the textures for the boy's genitals, which I previously pasted into the textures folder of my new Alt-Futa. If all goes well and UV-Swapper hasn't messed up by leaving blank areas in some textures seams (can happen, and then you'll have to retouch them in Photopea again, with stamp tool), when you're happy with how it looks, click the Save Preset button in the Alt-Futa Plugin, and it will save the texture settings for your new Alt-Futa. Regarding her/his shape, hair, and behavior, tweak the F Breast and F Glutes Physics as you wish (raise the dampers so her pecs and butt don't shake like jelly), and then create a new Appearance Preset of your girl transformed into a brand-new, hot like hell Alt-Futa boy, so that her/his morphs, physics, hair, etc. are saved.
Congrats! You now have a gorgeous boy who likes top and bottom... All that's left is to offer a kind, merciful thought to all those little persons who, since the creation of this game, have systematically neglected male figures and gay or REAL bisexual intercourse... when you get down to work, you might feel like I do. For any query, please don't hesitate to DM me, I'll be so pleased to help as much as I can. Have fun!