As per the law, STCL can be adjusted against STCG & LTCG and LTCL can be adjusted only against LTCG.
FnO trading is considered non-speculative business income & intraday is considered speculative business income.
You can set off losses of only FnO losses against the capital gains as it is a non-speculative income. Speculative losses can be set off only against speculative income.
- You can also set off losses from the “Income from Other Sources” head.
Refer to Set Off and Carry Forward of Losses under Income Tax - Learn by Quicko for more information.
Hope this helps.