not quite sure what you are asking? upon exercise if ISO no tax is due until sold and there is no election that has to be made.
see this link
https://www.schwab.com/learn/story/incentive-stock-option-iso-taxes-guide?msockid=23c003a0181a61f5227215a71c1a6311
there is an 83(b) election but that applies to RSUs subject to vesting. it does not apply to ISOs