In re applying 5th Amendment provisions to states, do you mean by incorporation in the *13th? Or by litigation? My understanding is, that took a very long time to find a footing OTL...
As I have said, not only the Fifth Amendment but virtually all of the provisions of the Bill of Rights except for the First Amendment and part of the Seventh could be viewed as
directly applying to the states--those are the only two amendments in the Bill of Rights that refer specifically to the
US government. Read literally, all the others could be seen as applying to state governments as well. Of course to so decide would mean overruling
Barron v. Baltimore but the Supreme Court does overrule decisions, and as I noted at
https://www.alternatehistory.com/forum/threads/barron-v-baltimore-decided-differently.409203/ Barron has always had its critics.
Besides the Bill of Rights, another possible source of protection for human rights against state-governments' intrusion in a no-14th-Amendment US would be the original Constitution's "privileges and immunities" clause: "The Citizens of each State shall be entitled to all Privileges and Immunities of Citizens in the several States."
https://www.archives.gov/founding-docs/constitution-transcript In a famous dictum in
Corfield v. Coryell Justice Bushrod Washington suggested an interpretation of the provision quite similar to what later would be called substantive due process: "The inquiry is, what are the privileges and immunities of citizens in the several states? We feel no hesitation in confining these expressions to those privileges and immunities which are, in their nature, fundamental; which belong, of right, to the citizens of all free governments; and which have, at all times, been enjoyed by the citizens of the several states which compose this Union, from the time of their becoming free, independent, and sovereign. What these fundamental principles are, it would perhaps be more tedious than difficult to enumerate. They may, however, be all comprehended under the following general heads: Protection by the government; the enjoyment of life and liberty, with the right to acquire and possess property of every kind, and to pursue and obtain happiness and safety; subject nevertheless to such restraints as the government may justly prescribe for the general good of the whole..."
http://press-pubs.uchicago.edu/founders/print_documents/a4_2_1s18.html
Finally, Congress might be held to have power to enforce fundamental rights on the states via the Guaranty Clause: "The United States shall guarantee to every State in this Union a Republican Form of Government..."
All this is even apart from the Thirteenth Amendment, which could (and has been) interpreted as allowing Congress to take action against "badges" and "incidents" of slavery as well as actual chattel slavery.