I did this recently. Had an FSA triple with 50/39/28. I got rid of the outer chain ring and used a 46T in the middle position and changed the inner ring from 28T to 30T.
The 46T is an Origin 8 and was made to be an outer chain ring so I had to install it backwards so the ramps and pins are on the outside which do not do anything.
Still it shifts pretty well. I changed the the FD to SRAM Force 22 and I have SRAM Red 10 speed rear shifter. the cassette is 12-36 so my higher gear is 46/12 which we spin out out 28 mph.
I thought it would be ok, but on some hills it is not high enough. My freehub won't fit an 11 speed cassette but I ordered one of these 11-36 11 speed cassettes that fit on a 10 speed freehub.
I have a spare Force 11 speed shifter so I will be using that.

https://velo-orange.com/products/11-speed-cassettes