No, the i3-9100F is not soldered; it has Intel's polymer TIM between the Die and the IHS.
However, the 9100"F" is not an overclockable "K" processor, and has no IGPU (Integrated Graphics Processor Unit). Moreover, 9th Generation non-K i3's are only 62 to 65 Watts TDP (Thermal Design Power), and don't have Hyper-Threading. Additionally, the 9100 and 9100F are lower clocked variants of the i3-9320 and 9300 and thus have lower power consumption which means lower Core temperatures.
Regardless, these i3's are Quad Core processors, which can exceed the thermal capacity of their packaged 65 Watt stock cooler. With an inexpensive mid-range aftermarket cooler, even when running AVX2 workloads, Core temperatures should remain below 80°C.
As such, it would be pointless to delid this processors.