Upvote:5
If the training you're going to receive is immediately work related (and why else would your employer pay for it?), then it's a permitted activity under a standard visitor visa:
23 Employees of an overseas company or organisation may receive training from a UK based company or organisation in work practices and techniques which are required for the visitorβs employment overseas and not available in their home country.
See the Visitor rules, appendix 3, paragraph 23.
When putting together your application, follow the documents guidance for business visitors rather than students -- work-relevant training is a business activity, not studying.