Thanks for your question. I will try to help.
The first problem is that you would not be able to get her a visa on the basis of your relationship unless you were to marry. This is because you must have cohabited in the same accommodation in a loving relationship for 2 years in order to be regarded as “unmarried partners” for the purpose of applying on a non-married relationship.
The second problem is that even if you were to marry you would not be permitted to count your partner’s income. This is because the financial requirement for a spouse/unmarried partner’s visa states that your partners income would only be permitted to count if she was already in the UK with permission to work.
So, it seems a visa based on your relationship is not possible at the moment.
The best thing to do, if her company is willing to transfer her here is to see if she is able to apply for a Tier 2 Intra-company transfer visa:
This is a visa whereby a sponsor employer licensed to sponsor migrants for tier 2 purposes transfer an employee to the UK for the purpose of employing them in a new role.
If the company is willing to sponsor her to do this and she meets the eligilbity criteria (https://www.gov.uk/tier-2-intracompany-transfer-worker-visa/eligibility) then this might be an option.
She could then work here, live with you hopefully for two years and then you could apply for an unmarried partners visa using her UK-earned income to meet the financial requirement.
I am sorry that I could not have better news for you, I do not agree with the law in this case but it remains the law nevertheless..
My goal is to provide you with a good service. If you feel you have received anything less, please reply back. Please remember to leave positive feedback using the stars at the top of the page.