Designing a LP filter in Simulink to match an existing discrete block

Hi,

I'm looking to design a low pass filter in Simulink to match the response of a discrete LP filter passed on to me in the form of a Simulink block.

Having fairly intermediate experience in creating filters I'm looking for some help on the best way to do this.

Characterising the existing filter using a chirp signal and a Bode Plot is fairly straightforward I think. Is there an efficient way of taking key information from the output of this and translating it into the Filter Builder App which is my strategy? This would allow me to specify a transfer function based on this.

Also, is it possible to use a LP filter/ transfer function in conjunction with a variable step solver given its output is strongly linked to the sample rate?

Thanks