For my cycle tour in Germany I bought an Iron Roots Beechwood Performance T-Shirt. It was perfect! We ended up in a heatwave, cycling along the river Rhine, but the shirt behaved very well. No sweaty spots, nice comfortable an cool feeling and it stayed clean for several days, despite the sweat and suncream...
I am about to order a few more.
And as a biologist, sustainability adept and inhabitant of this beautiful planet, I want to emphasize, over and over, that plastic-free clothing is the only way forward.