Yeah! After Diploma in Mechatronics you can obviously go for the BTech in CSE lateral entry. In general, there are no influence of the Diploma course as an eligibility to pursue a BTech course through Lateral entry. So you can do in general, any course of BTech. Although, I would recommend you to check the eligibility of the college in which you are trying to get admission in.

To know more about Lateral Entry examination, visit the link below:

https://engineering.careers360.com/articles/what-btech-lateral-entry-eligibility

To know more about CSE as a career, visit the link below:

https://www.careers360.com/courses/computer-science-engineering-course

I hope this answer helps. All the very best for your future endeavors!