You can go with either construction, but neither is quite right. You can either use "Unlikely as it may seem" as a sentence adverb in the first, or you need a conjunction such as "but" between the two independent clauses of the second.

Hi, Your only issue is the firstly word, which should be "Unlikely" and not "unlike". So the correct sentence is: "Unlikely as it may seem...." Unlikely means there is a low chance that something might happen. For example: "It is unlikely that the sun will disappear tomorrow" The word "Unlike" means "not similar" aka that one thing doesn't resemble another (in appearance or other quality) For example: "The jasmine shrub is unlike an olive" or "My mother is unlike my father" (in terms of personality or appearance)