If it ends in U, HQ, or H, those chips are soldered. HK (unlocked multiplier) is also soldered (rare, only in enthusiast notebooks). The CPU type is a more reliable clue then speculation - go off of the EXISTING CPU to know for sure, not speculation. With this laptop, post-HSW is soldered and HSW will either be modular (Socket G3/37-47W TDP depending on if it is a 2C/4T dual-core OR 4C/8T quad core) or soldered (ULV series - 15W). Example HSW CPUs are: i5-4310M (Socket G3/37-47W Modular) or i7-4600U (ULV/soldered 15W).
With Intel, anything mobile post HSW is soldered, including mobile Broadwell as this was predominantly a mobile platform with some enthusiast desktop chips. AMD did it years earlier for some (Ex: C series netbook CPU), now all of their mobile chips have also been soldered since ~2014-15, similar to Intel. I get CPU modularity has advantages; I held onto HSW for the Socket G3 chips until it was so old the issues were hard to ignore, like not being able to use NVMe SSDs (M.2 AHCI works on HSW but not NVMe - 6th gen or newer is required to use an NVMe SSD) despite the weight and thiccness of the computers. After NVMe got cheap, the cracks were permanently opened for me beyond repair. The speed of NVMe makes up for the soldered CPUs for me (and many others). NOTE: While NVMe is nice, if you still value modular CPUs you can still get by with a Socket G3 HSW notebook - just keep the issue of NVMe support in mind when buying one, and the original batteries tend to be fried at this point - my E6440 (Socket G3) battery failed ePSA at one point so it’s shot and is bipolar about if it’s EOL (per ePSA) or tired.
At this point, the only people who honestly care about the issue of soldered vs. modular think you gain a lot of performance with a CPU upgrade when you never, ever do. It just preserves your old motherboard in the rare event of a bad CPU.
TECHNICALLY you can replace the soldered CPUs, but you need to get a schematic and make sure the board has the right resistors and VRM coils, have a new CPU (or a used reball) and a reflowing machine for soldered ones... Not practical for a DIYer.