Trans men and trans masc people can be: short, feminine, curvy, high voiced, have interests that are 'atypical' to strict masculinity as well as typical interests, cute, have long hair etc
Trans women and trans femme people can be: tall, broad, into typical and 'atypical' feminine interests, deep voiced, strong, short haired, gruff, flamboyant, effeminate etc
Neutral people can be: short, short haired, afab, 'masc' dressed, not much into 'feminine' things etc
BUT when you only target these kinds of characters for trans canon or headcanon, it may be important to question wether they've become stereotypes, possibly negatively so.
These kind of people are as likely to be trans or non-binary as people exactly the opposite or in the middle.
So basically, it's fine to have characters like this as trans/non-binary but even if you're not cis yourself you should challenge why we see these kinds of people as not cis, but rarely or never treat the opposite (or middling) type of person the same way. It's also important to acknowledge that people can be cis and gnc but that's a separate post.