TTS and MTM are two different things.
For an individual or entity to make an MTM accounting election, AND HAVE IT APPROVED BY THE IRS, the individual or entity must qualify as a "trader" or a dealer in the eyes of of the IRS. Enter TTS which has no "official" definition other than through case law study.
Worth mentioning, is the fact MTM accounting is PERMANENT unless permission is granted by the IRS to change accounting method. TTS is a tax year-by-tax year qualification.
Seek professional advise.