No, there are decades left of the J-20/J-35 being the "lo" side of the mix for manned fighters.
That said, manned fighters themselves might be kept around just as backups in a world of AI autonomous fighting machines.
Not obsolete in the sense they are no longer competitive but obsolete in the sense there isn't much sense to procure them further, once J-XDS hits the LRIP phase why would the navy keep buying J-35s? The navy unlike the air force doesn't operate thousands of fighters so it doesn't take forever to replace old ones nor do they really need a hi-lo mix of fighters, at best by 2030 PLAN would be operating approx. 132 fighters on carriers plus a dozen or two extras for spare and training. As Cute Orca said, the navy only have so little fighters that they are willing to spend more money on the latest and greatest so IMO once J-XDS hits the market no more J-35 would be procured. So, if 2D TVC J-35 are ready the same time has J-XDS why would the navy buy 2D TVC J-35 and not just straight up the much better J-XDS?
won't take much time as they are working on different TVC nozzles for years.
The thing that I'm most worried about is that adding 2D TVC might necessitates some airframe changes for the rear end which will almost definitely add years to development time unless they decide to just jam on one of those weird not-so-2D 2D thrust vectoring engines like on the Su-57M