I found these doing VERY minimal research:
•Ey/Em/Eir (1975, created by Christine M. Elverson)
•E/Em/Es (1890, created by James Rogers)
•Per/Pers/Perself (1976, Used in a novel by Marge Piercy)
•Thon/Thos/Thonself (1858, Created by Charles Crozat Converse)
•In 1789, William Marshall confirmed the use of both“a” and “ou” as a replacement for he/she/they and even i.
•Co/Coself (1970, created by Mary Orovan)
•Ne (1850, appeared in print in 1884)
•En (1868, mentioned by Richard Grant White)
•Hae/Haes(Hais)/Haim (1884)
•Tha/Thare/Them(Thon) (1885)
•Zyhe/Zyhe’s/Zyhem (1885)
Sources for these as well as many others that I didn’t add due to the list getting too long can be found here.
An interesting note is that in the modern language a lot more people use neopronouns then you would expect!
•Yo is a majorly African American pronoun coined in 2004 and used by Middle School students In Baltimore, Maryland.
•Fae/Faer, coined in 2014, is used by 4.3% of participants in the 2019 Gender Census.
Plus a vast variety of newly coined pronouns that you will have seen commonly floating around!
Neopronouns have existed and been recorded for a long time, they are not a new concept, nor are they mogai or a tumblr concept. They are not modern, there have just been many modern adaptions to already existing pronouns.