The vast majority of Timeshifted cards from Time Spiral are listed as not legal in Modern.

Gatherer search for set: Timeshifted, format: NOT Modern lists 117 Timeshifted cards as NOT LEGAL in Modern. They are not listed as banned; they are simply not listed as legal.
Gatherer search for set: Timeshifted, format: Modern lists 5 cards.

The five legal cards are Disenchant, Dragon Whelp, Fiery Temper, Gaea's Blessing, Tormod's Crypt. These five are the only cards to be printed later in a standard-legal (or modern-legal) set: https://scryfall.com/search?q=in%3Atsb+date%3Etsp+%28st%3Acore+or+st%3Aexpansion%29

The keen-eyed among you would notice this adds up to 122, but there were only 121 Timeshifted cards. The extra is because Assault // Battery is listed twice: Assault is one result, Battery is another result.

WotC Submission Number: None provided