Winter clothing [Tights over shorts/bibs]

Defeet wool knee warmers or

This is a common place to get cold. If you want a layer - Defeet makes a pretty unique wool knee warmer that you can wear almost upper thigh to just below the knee or lower thigh to ankles.

Another option is to get some space between the wind layer and your thigh. I’ve bought grid fleece long underwear and just cut them down into shorts.

Are the trousers tights or pants? Is there a shell layer or is all just fleece material? If fleece/knit material, you need a wind blocker there. Short term, you can try putting a light layer of wax on the front thigh while you’re wearing them. This should clog some of the holes in the knit.