Ask HN: How would you target businesses with this software service?

Say you've built an internal communication application like Gmail, Outlook, Microsoft Teams, Slack and Zoom.

With an app like that, how would one get their first few users?

With it being a crowded, well-established market, would pre-established businesses be willing to ditch what they already use for (what seems like) a small benefit? or if not how would you target newly-formed businesses which haven't made a choice yet? could you target within-business teams rather than whole businesses?

Would you choose advertising, content marketing, talking to people (where would you find people to talk to?), or something else?