Well, you see, I assumed that, like a lot of different forms of conflict in the Exalted setting, the context of the conflict would change the nature of the conflict. There's individual martial or social combat, then there's mass martial or social combat, and when individual cities and states have reason for conflict they fight in their own distinct way, too.
Which meant that when I plug Exaltedtech into the setting, I was kinda assuming that conflicts involving mechs would take that context. But I forgot about the Exalts. I forgot that it is possible, nay, likely, that a Solar would look at a walking pile of guns, armor, and bad attitude, made out of thousands of pounds of steel and magical materials, and think,
"The optimal strategy in this situation is to hit it with my sword."
"...Really hard."
So, off the top of my head, lets come up with a new type of damage, Mech-scale damage, or M for short. The Damage of every weapon in Battletech will be suffixed by this tag.
For example, the small laser now does 3M damage.
The conversion rates for this damage in other contexts, like character vs. battlemech, as follows:
1M -> 5L
1A -> 1M
5L -> 1M
10B -> 1M
So, unspecified aggravated damage is just as potent against battlemechs, and heroes have to work pretty hard to hurt mechs.
This is only for small-scale conflicts, or characters acting as solo units in a Mech-scale battle. Like mass combat, the presence of a whole lance can force ther context on the battle. Same as an angry mob against a bandit with a mech, the mob becomes units of infantry with appropriate record sheets.
This is only a first draft, but I think It should work. I based my calculations off of the concussive essence cannon in Wonders of the Lost Age, figuring that a Large CEC is roughly equivalent to a small laser.
If this works, I'll add it to the first post. Thanks for asking!