Long time no see!

しばらく for a while (usually used in negative connotations)
ひさしぶり for a while (usually used in positive connotations, closer to “long time no see!”)
 #おひさしぶり = honorific way to say ひさしぶり、but usually it is also used in casual speech.

以前お会いしてから、 しばらく ですね~
It’s been a while since we have last met.

ひさしぶりですね! お元気ですか?
Long time no see! How are you today?

#Justin Palmer 1.7.17