I see but given there's YS Net watermark in the trailer it's still developed and published by third parties (most likely by YS Net and ININ Games).
The franchise is still belongs to SEGA though given to the second watermark.
So no different than Shenmue III (or Streets of Rage IV and Wonder Boy: Dragon's Trap).
Here comes more various balls, rackets, shoes, hats, chairs collectibles ...
It's like they had various model resources they didn't know what to do with, but couldn't get sponsored or promotions from other video game franchises to make collectible figurines from.
So just... random junk for collectibles.
I mean, Shenue I-II had Sega characters for collectibles and they were iconic and made me want to spend ¥100 for them. But Shenmue III just had random junk. I guess they made an Achievement as means to encourage collecting them.
I know Yu Suzuki wanted his Shenmue series to himself, but it's just not the same without Sega.
YsNet responded to the viral Shenmue IV video by saying that video has absolutely no connection to them.

Source: https://x.com/YSNET_Inc/status/1997938996677394595
Oh, I guess it was fake then.