I earned funds (from stock) that I need to nominate to another person (ex-wife). There is an attachment to Sched D where I put "N" for nominee. Where to find in turbotax?

I'm not sure why you think this income is taxable to her rather than to you. please clarify

if part of the property settlement but sold by you. then I believe it's your income. it's the cash from the sale that was transferred. alimony for a post 2018 (also pre 2019and modified) divorces is no  longer deductible so if you're saying you sold securities to pay her alimony, the above applies. 

if you are correct on it being her income then; 

see this link for how to report  on schedule d

https://ttlc.intuit.com/community/business-taxes/discussion/how-do-i-enter-nominee-amounts-on-schedule-d-i-have-several-equity-sales-st-and-lt-i-am-a-50-owner/00/513927 

See the separate specific instructions for each form.

Nominee/middleman returns. Generally, if you receive a Form 1099 for amounts that actually belong to another person, you are considered a nominee recipient. You must file a Form 1099 with the IRS (the same type of Form 1099 you received) for each of the other owners showing the amounts allocable to each. You must also furnish a Form 1099 to each of the other owners. File the new Form 1099 with Form 1096 with the IRS Submission Processing Center for your area. On each new Form 1099, list yourself as the “payer” and the other owner as the “recipient.” On Form 1096, list yourself as the “Filer.” A spouse is not required to file a nominee return to show amounts owned by the other spouse. The nominee, not the original payer, is responsible for filing the subsequent Forms 1099 to show the amount allocable to each owner.

the 1096 is the transmittal form that must accompany the 1099's not only security transactions but also 1099-div or 1099-int that goes to your ex.

The IRS website provides for informational purposes a copy of the 1096. It appears in red, similar to the official IRS form. The official printed version of this IRS form is scannable, but a copy, printed from

this website, is not. do not print and file a Form 1096 downloaded from this website; a
penalty may be imposed for filing with the IRS information return forms that can’t be
scanned. See part O in the current General Instructions for Certain Information Returns,
available at www.irs.gov/form1099, for more information about penalties.
To order official IRS information returns, which include a scannable Form 1096 for filing with
the IRS, visit www.IRS.gov/orderforms. Click on Employer and Information Returns, and
we’ll mail you the forms you request and their instructions, as well as any publications you
may order.

you may want to consider using a pro to prepare the 1096/1099s