The pop star resumed the international leg of the 'Eras' tour Wednesday, popping up at the Tokyo Dome for her regular full set of songs in front of a packed house ... and thousands of fans. From the looks of these photos, she hasn't lost a step since November.

TayTay was rocking all her usual costumes and wardrobe for the concert -- and she was full of energy, just like she usually is. And yes ... the Swifties got there early to take it all in.

Remember ... this is the first time Taylor has performed in a setting like this since right around Thanksgiving time -- when she had a few gigs lined up in Brazil ... some of which ended in tragedy.

Once she wrapped those shows, though, she came right back to the States and spent the rest of the holidays with Travis Kelce -- as well as friends and family ... and she's had a nice long break from her professional life these past couple months.

The grind, however, kicks off anew now ... and she'll be regularly performing again all over the world through the rest of this year -- albeit, with some brief gaps here and there.

As for this upcoming weekend -- when Travis and the Chiefs play the 49ers in the Super Bowl -- Taylor is expected to show up for that come Sunday ... she'll have plenty of time.

Granted, she might be jet-lagged -- but by all accounts, TS will be front and center to cheer on her boyfriend like she has been for much of the NFL season. Her final show in Tokyo finishes up on Saturday ... after which, she can just jet back here with no real pressure.

In the meantime ... her Tokyo fans get to enjoy her for the next few days. Win-win!