If software artifact is patented and then licensed under Apache Software License 2.0 what are the limitation due to the patent?
It would depend if you are the patent holder and if you are the licensor or a contributor.
If you are both the patent holder and either the licensor or a contributor then per section 3 you are eventually granting a patent license.
If you are neither of these and are just the recipient, then this patent is licensed to you but this is a limited license. Again per section:
[...[ where such license applies only to those patent claims licensable by such Contributor that are necessarily infringed by their Contribution(s) alone or by combination of their Contribution(s) with the Work to which such Contribution(s) was submitted.
So this is limited to the scope of what the software does which could be quite limited depending on how you read a given patent.
The license granted per section 3 again states:
[...] patent license to make, have made, use, offer to sell, sell, import, and otherwise transfer the Work [...]
I would interpret
make and have made as a license that would allow to create "infringing" work in other languages. The case of doing modifications does seem implied there too, but this is just a wild take.
As always with patent, you should consult an attorney.