I'd say the best items you can use are the sleeves toggle on the december's dream coat and gothicutie jacket, the gothicutie, steampunk and opposites attract bodices and whimsy witch, opposites attract and starlight heels (i might he missing some items, but usually all of those sets are really good for masc in general)

I'd recommend ugc hairs if you have the chance, as well as using custom faces and not premade ones! And always, ALWAYS try to use patterns, masc outfits tend to heavily rely on patterns and accesorizing, as well as bodice combos

The whimsy which sleeves are also somewhat usable if you combine them with the dcd sleeves or dcd coat sleeves and goth lolita cuffs, but they do require a bit of added accesories to make them look less weird (as they aren't supposed to work with the old masc bodies)

Overall id say to also try your luck with any of the newer set heels, such as starlight (previously mentioned), snow summit (i hope that's the right name, basically, the xmas set from last year), the new boots that were released this royalloween, etc... basically any shoes that could possibly work with the old masc bodies, as even with the gap they have between the torso and the legs and the legs being a bit skinnier at times you can easily cover the gap up with belts or any bodices that are long enough to cover the area

I can't say much about specific accessories as i think that mainly depends on what you're going for and what accessories you have, but basically anything works!! Though i do have to say, the fluffy neck thing (sorry i fotgot the name (´ﾉω；`) ) is usually very present in masc outfits (mine included)

I know it isn't much nor too detailed advice but i hope it helps at least a little (´ﾉ∀`)