Some writers are using plead as a noun. It’s a verb.
One meaning of the verb plead as a legal term is
To put forward any allegation or formal statement forming part of the proceedings in an action at law.
In general use, the verb plead means
to make an earnest appeal, entreaty, or supplication; to beg, implore.
The noun plea has similar legal and general meanings:
1. A suit or action at law; the presentation of an action in court.
An urgent, emotional request, an entreaty; (also) an unarticulated appeal.
Used as a verb in place of plead, plea can be regarded as a regionalism (Chiefly Eng. regional [north.], and Sc. Now also U.S.):
If you plea guilty and then later in another hearing say th(at you didn’t do it, can you be charged with perjury? –example of U.S. usage in OED
Using the verb form plead for the noun plea, however, is jarringly nonstandard:
A Plead to Sinners –title of a poem on a religious site
A plead to ban homophobia –headline on a college site
A plead for help –part of a blog title
In each of these examples, the word wanted is plea.