Is it okay for me to sponsor my husband to UK for 6 months

Under UK Immigration Rules, the onus is on the applicant to demonstrate that they fulfil the relevant visa requirements.

The Rule relating to sponsorship states:

V 4.3. In assessing whether an applicant has sufficient funds under V 4.2.(e), the applicant’s travel, maintenance and accommodation may be provided by a third party only if that third party:

(a) has a genuine professional or personal relationship with the applicant; and

(b) is not, or will not be, in breach of immigration laws at the time of the decision or the applicant’s entry to the UK as a Visitor; and

(c) can and will provide support to the applicant for the intended duration of the applicant’s stay as a Visitor.

Source: https://www.gov.uk/guidance/immigration-rules/immigration-rules-appendix-v-visitor

If you meet those requirements, there is nothing to prevent you from sponsoring your husband’s application. However, he must still demonstrate that he is a genuine visitor as described in

V 4.2. The applicant must satisfy the decision maker that they are a genuine visitor, which means the applicant:

(a) will leave the UK at the end of their visit; and

(b) will not live in the UK for extended periods through frequent or successive visits, or make the UK their main home; and

(c) is genuinely seeking entry or stay for a purpose that is permitted under the Visitor route as set out in Appendix Visitor: Permitted Activities and at V 13.3; and

(d) will not undertake any of the prohibited activities set out in V 4.4. to V 4.6; and

(e) must have sufficient funds to cover all reasonable costs in relation to their visit without working or accessing public funds, including the cost of the return or onward journey, any costs relating to their dependants, and the cost of planned activities such as private medical treatment. The applicant must show that any funds they rely upon are held in a financial institution permitted under FIN 2.1 in Appendix Finance.

To do that typically means showing ties to home country (a job, family) and a stable lifestyle there. Based on your question, your husband would not be able to do that, in which case your ability to sponsor him becomes irrelevant (and is actually most likely a hindrance, since he would be perceived as having a strong motivation to stay in the UK illegally).

This UK visa refusal on V 4.2 a + c (and sometimes 'e') covers pretty much everything you need to consider if he applies for a Standard Visitor visa.

You may have misunderstood the advice you received.

There are two reasons that your husband has to provide financial evidence with his visa application. The immediate one is that his visit will cost money, and that money needs to come from somewhere. This reason you can cover by you or your mother sponsoring him (assuming you have the means yourself).

The second reason is that they want to understand his personal circumstances. To be sure that he has a compelling reason to return to Egypt after his visit, ideally your husband would demonstrate that he has a well-paid, above-the-table job in Egypt. One that earns him enough to afford a standard of living in Egypt that is more comfortable than having a badly-paid job in the UK. There also is a side aspect of demonstrating that he is a responsible, law-abiding guy who keeps decent financial records and pays his taxes, etc.

Having a sponsor doesn't help at all for this second part. Thus, while you or your mother can sponsor your husband, his application would still be very weak. Unless there are some remarkable circumstances in his favour, I find it difficult to imagine him being successful without the above-mentioned well-document and well-earning job in Egypt.

As post scriptum, please also be advised that applying for a six month visit seems ill-advised. If your husband can stay away from Egypt for six months, it will be extremely difficult to make the case that he has a compelling reason to go back.