Is this the right way to express concession using inversion?

It sounds awkward because the first part is not a complete thought (it's a modal verb introducing a subjunctive phrase), and needs to be joined to the second part somehow, for example, with though or but:

Though the emotions may be controlled, it is not easy to do that.
The emotions may be controlled, but it is not easy to do that.

There is a subtle difference, I think, between the emotions and just emotions, and in this context omitting the sounds a little bit better, because you're talking about emotions in general:

Though emotions may be controlled, it is not easy to do that.

The final that also sounds a bit formal, or just odd. Typically we say do that for emphasis, especially to express contrast between two things:

Don't do that! Do this instead.
He told me to leave, but I didn't want to do that at all.

In this context do so may flow better, and it has the same meaning.

Though emotions may be controlled, it is not easy to do so.

What you may be thinking of is this:

• Should France agree to transfer control of the operation to NATO, this might improve relations with Turkey.

• Had there been more frequent security checks in Fukushima Daiichi, the current crisis would have been much less serious, so say some foreign experts.

• I'd never give them a single penny, even were I a rich man. (old fashioned)

• Be that as it may, this house is too expensive.