Brazilian taxpayers with assets abroad have specific reporting obligations to the Receita Federal Brasileira (trough a Declaração de Ajuste Anual de IRPF) and, depending on the amount of assets abroad, to Banco Central do Brasil (trough a Declaração de Capitais Brasileiros no Exterior (“DCBE”)). You may check if you need to report your assets to the Brazilian Central Bank here: https://www.bcb.gov.br/estabilidadefinanceira/cbe.
If you are not a Brazilian taxpayer, you may still have reporting obligations in your country of residence and citizenship.