use pageant as ssh agent
Windows’s own port of OpenSSH uses the same mechanism as Pageant to talk to its SSH agent (Windows named pipes). This means that Windows OpenSSH can talk directly to Pageant, if it knows where to find Pageant’s named pipe. When Pageant starts up, it can optionally write out a file containing an OpenSSH configuration directive that tells the Windows ssh.exe where to find Pageant. If you include this file from your Windows SSH configuration, then ssh.exe should automatically use Pageant as its agent, so that you can keep your keys in one place and have both SSH clients able to use them. To refer to this file from your main OpenSSH configuration, you can use the Include directive. For example, you might run Pageant like this:
pageant --openssh-config C:\Users\youruser\.ssh\pageant.conf
and then add a directive like this to your main .ssh\config file:
Include pageant.conf
Try if bitwarden agent script works in this setup for pageant