Can I add missing info on imported T5008 for adj cost, expenses ? Will Sch 3 Supplementary sheet be generated from edited T5008s , without using Capital Gain tab?

[TurboTaxJared]

Yes, you can enter adjusted cost base (ACB) in TurboTax T5008 page even if you don't have it on your T5008 slip. Without ACB, your capital gains will not be calculated accurately. It is understandable that you might feel uncomfortable to add it there because the amount is not on the slip, but it's ok because many T5008 issuers don't include this amount on the slip and usually the recipient has to obtain/calculate the information.

You don't have to enter this information again in the Capital Gains section. Review the information below:  https://turbotax.community.intuit.ca/replies/3549415