Perl 6, 34 32 bytes

{[~] flat roundrobin |$_».comb} 

{roundrobin(|$_».comb).flat.join} 

A lambda that takes an array of strings as argument, and returns a string.

Perl 6, 34 32 bytes

{[~] flat roundrobin |$_».comb} 

{roundrobin(|$_».comb).flat.join} 

A lambda that takes an array of strings as argument, and returns a string.

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Perl 6, 34 bytes

{roundrobin(|$_».comb).flat.join} 

Perl 6, 34 32 bytes

{[~] flat roundrobin |$_».comb} 

{roundrobin(|$_».comb).flat.join} 

A lambda that takes an array of strings as argument, and returns a string.