BCH is a hard fork of BTC and shares the same transaction history up to the point of the fork.
The BCH hard fork took place on 1 August 2017.
The main differences between BTC and BCH is the increased block size supported by BCH and the adoption of Segregated Witness by BTC.
CashAddr address format
On 14 January 2018, Bitcoin Cash updated their standard address format, while maintaining compatibility with the old address formats. The new address format is called CashAddr. It has the following form:
BCH (reference address): bitcoincash:qpm2qsznhks23z7629mms6s4cwef74vcwvy22xxx6a
OneKey only supports the new address format. converting between CashAddr and the old address format requires you to do the conversion yourself.