Have you considered using shirt stays? I prefer the ones that go under your foot but the ones in the picture work too. Keeps the shirt tucked in and gives you a more professional look. I would think that with shirt stays, you'd be able to wear over the shirt suspenders.
The under garment suspenders came in and despite an issue with pokey plastic that I used a razor to shave off, I couldn't be happier with how they work. Wore them for two days now and haven't had my pants stay in place this well ever. And I don't have to tuck in my shirt.
Have those from when I was in the USAF. Thank goodness only had to wear "blues" maybe a few times a year. Had one come loose from my sock once. Was a front one and it shot up my pant leg at about 750mph. I saw stars and dropped to the ground, felt like a mule had just kicked me in the equipment.
Just ordered and received a pair of ballroom jeans. They are definitely built tough and roomy. Can't wait to try them out at work.
Gave them away for Christmas presents. My sons both work in construction. They really like being able to bend and not be restricted.