My answer is US-centric and my discipline is Statistics.
Yes, you should absolutely list any grant experience on your CV. Be clear about the status: I like to use "In Prep", "Pending", "Awarded", "Not Awarded".
Regarding "I fear that I might need to justify a failed grant if I do not get funding.", this is the complete opposite of the attitude that you should have. Committees will be looking for evidence that you will be able to get funding in the long term. The best way to show that you're serious about acquiring funding is to submit proposals. Everyone is aware that being awarded grants is 1) really difficult 2) very random. In my experience, having a grant submitted which was not awarded is viewed as a very positive thing. It is not a "failed grant": once you have a project description, you can improve and resubmit in the future. The people who get lots of funding over their careers submit many grants and have many of them go unawarded.
Even having multiple unawarded grants would still be viewed positively. Yes, presumably, if you had submitted 100 proposals and they were all rejected, that would look weird. But so long as you are taking the proposals seriously, it is essentially not possible to have this problem early career.