Solution 1:

Out of context, the meaning of "schematic claims" is unclear. But when you look at the whole article, the meaning of this statement is fairly unambiguous.

At the end of section 2.1, "Feminist Beliefs and Feminist Movements," the author writes,

Given the controversies over the term and the politics of circumscribing the boundaries of a social movement, it is sometimes tempting to think that the best we can do is to articulate a set of disjuncts that capture a range of feminist beliefs. However, at the same time it can be both intellectually and politically valuable to have a schematic framework that enables us to map at least some of our points of agreement and disagreement.

(Stanford Encyclopedia of Philosophy, emphasis added)

In section 2.2., we find "In an effort to suggest a schematic account of feminism, Susan James characterizes feminism as follows..." (emphasis added)

Finally, in 2.3 (in addition to the portion quoted in the question), we read,

Following [bell] hooks’ lead, we might characterize feminism schematically (allowing the schema to be filled in differently by different accounts) as the view that women are subject to sexist oppression and that this is wrong.

Thus, in this context, it appears that "schematic claims" are claims related to, or which are a part of the schematic framework of feminism that the author is creating.