I built a hallway bench from mesquite wood with iridescent blue dyed epoxy resin where the old rotted wood was. I got the idea from u/ryan820 and his redwood seat. Link to
Solidifying rotting wood in a log cabin with Epoxy.
FASCO STOP ROT EPOXY - Special Low Viscosity Resin for Penetrating and Stopping Wood Rot - Gallon and Quart Kits Available
PC Products 24 oz. PC-Rot Terminator 240618 - The Home Depot