I know that markdown is supported by the value of the HeroCard text field, although I could not get it to work (tested on MSTeams):

the code
this.bot.dialog("sendCard", (session, args, next) => {
session.sendTyping();
const card = new builder.HeroCard(session);
card.title("Title");
card.subtitle("Subtitle");
card.text("This is some *mardown* text! \n\n - one \n\n - two");
const msg = new builder.Message(session);
msg.textFormat("markdown");
msg.attachments([
card,
]);
session.endDialog(msg);
});
I am wondering how I can achieve this formatting (from the mailclark boot in MSTeams):

As you can see, this is a carousel of what, in my opinion, might be HeroCards, but they are formatted with bold, code, and unordered lists in new paragraphs .
It seems like a known issue is that message attachments don't get formatting, but how can the guys in this community achieve this ?
Edit: An example of an unordered list:

Bold and code example:

source