Laowa 100 f2.8 2:1 is the best 100mm Macro I tried if working distance isn’t paramount. All internal, the overall length doesn’t change like many other Macro lenses do when you increase magnification. No IS or AF. Speedlight+Diffuser is very much recommend even with IBIS. My Aug 2 2021 observations were taken with Laowa 100 f2.8 on a Sony A7ii body, all manual.
The Canons are well reviewed but I’ve not tried them myself, though looking at some direct comparisons the results don’t seem to justify the cost of the canon glass to me.
I’ve used Tamron 180mm f3.5 extensively first half of 2022. Currently settled on Sigma 150mm f2.8 + Nikon 2x TC. All macro entries since May 2022 were taken with Sigma 150mm+ Nikon TC, as well as few birds.
I carry a contractor bag, solves any potential issues with not having weather sealing.