Pure, unadulterated bardolatry.

ladybird. Yes, Romeo and Juliet is the earliest recorded use, but the word was almost certainly in wide oral use when Shakespeare wrote his play.

Out of interest, how is this determined?

half-blooded. Shakespeare may get credit for the adjective, but the noun is half a century older.

ie the noun half-blood, right?

Of the six that you give as fairly firm Shakespearisms, five appear to have been formed in regular and unspectacular fashion from pre-existing English words and affixes.

I am curious about the sixth, scuffle. Etymonline gives it from 1570, from scuff, “of Scandinavian origin”. ODoE says “late 16th century, probably of Scandinavian origin, compare with Swedish skuffa ‘to push’.

Out of interest, how is this determined?

It’s a term of endearment and a bunch of writers in the closing years of the sixteenth century all started using it at about the same time. Romeo and Juliet is, as far as we can tell, the earliest surviving example, but not by much. That points to it being in common use.

Yes, the noun half-blood.

It is the noun scuffle that we’re concerned with here. It comes from the verb, which the OED has from 1579 and which probably has a Scandinavian origin. All Shakespeare did was noun the verb. Hardly a feat of linguistic derring-do.

Well, that’s six out of six, then, all quite pedestrian.

I suppose it makes sense that the published scripts of plays should contain some of the earliest written records of words that had long existed in spoken English.