With BRICS, other currencies may be integrated. China also have a pix-like wechat Russia has a pix-like "BRICS Pay" And those systems can be integrated. PIX

With BRICS, other currencies may be integrated. China also have a pix-like wechat Russia has a pix-like "BRICS Pay" And those systems can be integrated. PIX QRCode protocol already have a "currency" field, that currently only support the constant value of "BRL" USA probably will continue to use check and printed money like the ancients do.