The Capital Gain figures are different for two funds where the cost base information is the same.
Where the investment was purchased on the same date with identical quantity and cost in two different funds, the difference is due to each fund using a different Parcel Match Method.
Navigate to Fund Level > Settings > Investment Register
- Check the Parcel Match Method
Fund 1 has Parcel Match Method set as First in, First out and Fund 2 has Parcel Match Method set as Minimise Taxable Gain.