A substitute foot with two accents is?

Trochee would be one; check the link for more. More importantly, think about the over-all rhythms of Words and groups of Words without slavishly following the ancient Greek forms. They are useful to be sure, but unless you have a specific reason for exploring and using them, don't consider them rules that cannot be broken. If you want to see a possible outcome resulting from slavish classical scansion, see how many older greeting card verses you can read and take seriously as anything more than precious sentiment. They are like a cotton candy overdose; far too sweet and mostly air.