I haven't played it extensively with any good Tsubaki players (I haven't met any good ones yet) But what I have seen is that Tsubaki can shield charge right through steiner setups and just stop the lasers and force block from you and or, damage. Tsubaki being up close in this matchup isn't in your favor. Your moves aren't exactly what we like to call fast.
Reversal DP or reversal Omihikane helps but these are all baited eventually. Tsubaki's 5B really locks down most of your options, and you have to keep blocking when she's up close. And if you block, lasers aren't coming out, explosions aren't happening, and you are in danger of being hit. Mu is a mid range character, and you have to keep Tsubaki there.
A healthy chunk of j.C will stop most airdash attempts from Tsubaki (Until I find something to beat it) On hit just send em to the ground and start pressuring with steiners and 5C. If she DP's out you could always block and/or backdash.
I usually try to set up a small diamond of steiners and keep my motions ready to explode em in case I see a shield rush coming my way. Or an airdash.
It's a pretty ugly match to me. Tsubaki doesn't need to respect lasers all that much.