There's a further distinction between male-sexed individuals who enjoy crossdressing and those who identify as female and dress accordingly. Only the latter group is trans (and is so independent of what they wear)
Apologies to any nuance of language I've missed here, as I'm sure this could be nitpicked to death.
While both acknowledge that gender is fluid personal interpretation of identity, to drag (female impersonation, but there are women who drag as men), gender identity is a joke to be made fun of and celebrate, but being transgender takes gender identity seriously.
They can be expressed by the same people (see Peppermint who won 2015's RuPaul Drag Race, she is a transgendered woman who competes in drag competitions), but they can just as often be in conflict.
Mostly. In not all cases and for not all people, and I'm probably wrong.