Processing payments of over $1 million per transfer

The platform I’m building needs to facilitate electronic transfer of funds of between $20k and $20m at a time ($AU). Clients (both sides of the transaction) will initially be limited to Australia

Can I please get your thoughts and recommendations on the following three things:

  1. Security - optimum bank account integration method
  2. Fee models of different providers (e.g. from what I can tell the fee model for Plaid and Stripe seems to be for smaller transaction amounts, and I’m not even sure if these are the right tools?)
  3. Any pre-existing plugins that supports 1&2 above - and if not, whether you know of another intermediary that might eliminate the need for me to build separate APIs with each Australain banking institution… (which isn’t feasible)

Of course any other related suggestions or pointers are welcome.

Thank you in advance!

Regards,

Brett

hmm…