The only middle name my husband and I have been able to come up with/agree on for [name]Liberty[/name] is [name]Eden[/name]. Any thoughts or suggestions?
It would help to know the surname to give you a full honest opinion. But [name]Liberty[/name] [name]Eden[/name] sounds okay, maybe a little hard, or sharp. But it depends on your particular taste i think. 
I love the nickname libby, so that is cute as heck imo hehe. I will suggest a few i would possibly use though these may ofc not be your style in return. I like a name to flow well. And sound pretty so…
[name]Liberty[/name] [name]Rose[/name]
[name]Liberty[/name] [name]Grace[/name]
[name]Liberty[/name] [name]Mae[/name]
[name]Liberty[/name] [name]Estelle[/name]
[name]Liberty[/name] [name]Faye[/name]
[name]Liberty[/name] [name]Corinne[/name]
I really like liberty [name]Eden[/name], beautiful, but I really like the name [name]Eden[/name] so I may be biased