Transferring BCX to other wallets estimated cost automatically set by Metamask is roughly around 0.000032 BCX with Medium priority.
Setting Metamask to High priority sending will increase the cost to 0.000042 BCX. Though you can also manually change the gas price by clicking the Advanced Options if needed.
Transfer between Metamask and Keplr
Keplr Wallet allows you to have 2 types of address, one that starts with blockx and the other starts with 0x. In order to transfer from Metamask to Keplr, you'll have to use the 0x address. Click on the Copy Address at the upper section of your Keplr wallet then copy the right destination address. BCX tokens transferred to either of the address will reflect on your account accumulatively.
This basically means that if you want to transfer tokens from your Metamask or other EVM wallets like Trust Wallet going to your Keplr Wallet, just paste the EVM Address in your Keplr account and paste it as a recipient in your EVM wallet such as Metamask.