Welcome to the Microsoft Q&A Platform. Thank you for reaching out & I hope you are doing well.
Unless you are using a Classic VNET/VPN Gateway, you should be able to use Azure CLI/Powershell in both CloudShell as well as local server.
The Default IPsec/IKE parameters are defined here. You can refer to this and validate if the default matches your requirement.
However, please note that custom policy parameters are supported only in the following gateway SKUs
- VpnGw1~5 and VpnGw1AZ~5AZ
- Standard and HighPerformance
This means, you cannot custom policy defined in a Basic SKU.
Hope this adds more clarity.
Cheers,
Kapil