You need to include 1099s that include Ohio and/or school district taxes withheld.
According to Common Filing Tips for Paper Filers in the Ohio Individual Income Tax (IT 1040) Instructions, you need to include verification for the withholding you claim on your return:
"If you have an amount on line 14 of your IT 1040 and/or an amount on line 7 of your SD 100, include copies of your W-2(s), W-2G(s) and/or 1099(s) that show your Ohio and/or school district tax withheld."
[Bolding mine.]
[Edited 3|17|2020 2:59 pm]