Hi,
The link you shared seems to refer to an older version.
In AX2012, you have for example the reversing entry feature available that creates an offsetting voucher on the day you specified.
Another reversal functionality can - for example - be found in the ledger account posting form where you can simply reverse a voucher by hitting this button
Note: The last 'reverse transaction' button is also available in AP, AR, etc. Even though it is available there, you can't reverse everything. As an example, transactions that have a relation to item transactions cannot be reversed through this functionality.
Best regards,
Ludwig