Hi Sam,
Thank you for your message.
Not many brokers offer Mexican stocks, so I can appreciate may be struggling to find suitable options.
However, Interactive Brokers is one multi-regulated broker that does provide access to the Mexican Stock Exchange (Mexican Bolsa). I also used its product search function (https://www.interactivebrokers.com/en/trading/products-exchanges.php#/) to check it supports Grupo Mexico.
There may be other brokers offering Mexican stocks as well, so I recommend doing further research. Equally, other traders on this forum may have suggestions.
James Barra